211222220 has 48 divisors (see below), whose sum is σ = 499516416. Its totient is φ = 74328000.

The previous prime is 211222217. The next prime is 211222223. The reversal of 211222220 is 22222112.

It is an interprime number because it is at equal distance from previous prime (211222217) and next prime (211222223).

It is a super-2 number, since 2×211222220² = 89229652443456800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 211222195 and 211222204.

It is not an unprimeable number, because it can be changed into a prime (211222223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8666 + ... + 22305.

It is an arithmetic number, because the mean of its divisors is an integer number (10406592).

Almost surely, 2^211222220 is an apocalyptic number.

211222220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

211222220 is an abundant number, since it is smaller than the sum of its proper divisors (288294196).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

211222220 is a wasteful number, since it uses less digits than its factorization.

211222220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31022 (or 31020 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

The square root of 211222220 is about 14533.4861612760. The cubic root of 211222220 is about 595.5431050826.

Adding to 211222220 its reverse (22222112), we get a palindrome (233444332).

The spelling of 211222220 in words is "two hundred eleven million, two hundred twenty-two thousand, two hundred twenty".