21212210211210 has 80 divisors (see below), whose sum is σ = 57150671630976. Its totient is φ = 5645343576672.

The previous prime is 21212210211149. The next prime is 21212210211221. The reversal of 21212210211210 is 1211201221212.

21212210211210 is a `hidden beast` number, since 2 + 1 + 21 + 221 + 0 + 211 + 210 = 666.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 25624294 + ... + 26439153.

Almost surely, 2^{21212210211210} is an apocalyptic number.

21212210211210 is an abundant number, since it is smaller than the sum of its proper divisors (35938461419766).

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

21212210211210 is a wasteful number, since it uses less digits than its factorization.

21212210211210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52063969 (or 52063960 counting only the distinct ones).

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

Adding to 21212210211210 its reverse (1211201221212), we get a palindrome (22423411432422).

The spelling of 21212210211210 in words is "twenty-one trillion, two hundred twelve billion, two hundred ten million, two hundred eleven thousand, two hundred ten".