121620215406 has 32 divisors (see below), whose sum is σ = 257580684288. Its totient is φ = 38150622080.

The previous prime is 121620215393. The next prime is 121620215407. The reversal of 121620215406 is 604512026121.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121620215407) 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, 801601 + ... + 941171.

It is an arithmetic number, because the mean of its divisors is an integer number (8049396384).

Almost surely, 2^121620215406 is an apocalyptic number.

121620215406 is an abundant number, since it is smaller than the sum of its proper divisors (135960468882).

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

121620215406 is a wasteful number, since it uses less digits than its factorization.

121620215406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148136.

The product of its (nonzero) digits is 5760, while the sum is 30.

The spelling of 121620215406 in words is "one hundred twenty-one billion, six hundred twenty million, two hundred fifteen thousand, four hundred six".