121211211210 has 32 divisors (see below), whose sum is σ = 291040568640. Its totient is φ = 32308138368.

The previous prime is 121211211193. The next prime is 121211211217. The reversal of 121211211210 is 12112112121.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 121211211210.

It is not an unprimeable number, because it can be changed into a prime (121211211217) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 861747 + ... + 992486.

It is an arithmetic number, because the mean of its divisors is an integer number (9095017770).

Almost surely, 2^121211211210 is an apocalyptic number.

121211211210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

121211211210 is an abundant number, since it is smaller than the sum of its proper divisors (169829357430).

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

121211211210 is a wasteful number, since it uses less digits than its factorization.

121211211210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1856422.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 121211211210 its reverse (12112112121), we get a palindrome (133323323331).

The spelling of 121211211210 in words is "one hundred twenty-one billion, two hundred eleven million, two hundred eleven thousand, two hundred ten".