321618581916 has 12 divisors (see below), whose sum is σ = 750443357832. Its totient is φ = 107206193968.

The previous prime is 321618581849. The next prime is 321618581951. The reversal of 321618581916 is 619185816123.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13400774235 + ... + 13400774258.

It is an arithmetic number, because the mean of its divisors is an integer number (62536946486).

Almost surely, 2^321618581916 is an apocalyptic number.

It is an amenable number.

321618581916 is an abundant number, since it is smaller than the sum of its proper divisors (428824775916).

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

321618581916 is a wasteful number, since it uses less digits than its factorization.

321618581916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26801548500 (or 26801548498 counting only the distinct ones).

The product of its digits is 622080, while the sum is 51.

The spelling of 321618581916 in words is "three hundred twenty-one billion, six hundred eighteen million, five hundred eighty-one thousand, nine hundred sixteen".