210121221212 has 36 divisors (see below), whose sum is σ = 452908353744. Its totient is φ = 84754776960.

The previous prime is 210121221203. The next prime is 210121221227. The reversal of 210121221212 is 212122121012.

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 31527464 + ... + 31534127.

It is an arithmetic number, because the mean of its divisors is an integer number (12580787604).

Almost surely, 2^210121221212 is an apocalyptic number.

It is an amenable number.

210121221212 is an abundant number, since it is smaller than the sum of its proper divisors (242787132532).

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

210121221212 is a wasteful number, since it uses less digits than its factorization.

210121221212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63061626 (or 63061617 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 210121221212 its reverse (212122121012), we get a palindrome (422243342224).

The spelling of 210121221212 in words is "two hundred ten billion, one hundred twenty-one million, two hundred twenty-one thousand, two hundred twelve".