21121211202210 has 96 divisors (see below), whose sum is σ = 62870470565760. Its totient is φ = 4819220792064.

The previous prime is 21121211202193. The next prime is 21121211202229. The reversal of 21121211202210 is 1220211212112.

21121211202210 is a `hidden beast` number, since 21 + 1 + 21 + 211 + 202 + 210 = 666.

It is a super-2 number, since 2×21121211202210² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 29101752 + ... + 29818691.

It is an arithmetic number, because the mean of its divisors is an integer number (654900735060).

Almost surely, 2^{21121211202210} is an apocalyptic number.

21121211202210 is an abundant number, since it is smaller than the sum of its proper divisors (41749259363550).

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

21121211202210 is a wasteful number, since it uses less digits than its factorization.

21121211202210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58921032 (or 58921029 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21121211202210 its reverse (1220211212112), we get a palindrome (22341422414322).

The spelling of 21121211202210 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred eleven million, two hundred two thousand, two hundred ten".