21620542065604 has 24 divisors (see below), whose sum is σ = 37878603436800. Its totient is φ = 10798084866240.

The previous prime is 21620542065583. The next prime is 21620542065641. The reversal of 21620542065604 is 40656024502612.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 107352552 + ... + 107553760.

It is an arithmetic number, because the mean of its divisors is an integer number (1578275143200).

Almost surely, 2^{21620542065604} is an apocalyptic number.

It is an amenable number.

21620542065604 is a deficient number, since it is larger than the sum of its proper divisors (16258061371196).

21620542065604 is a wasteful number, since it uses less digits than its factorization.

21620542065604 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231363 (or 231361 counting only the distinct ones).

The product of its (nonzero) digits is 691200, while the sum is 43.

The spelling of 21620542065604 in words is "twenty-one trillion, six hundred twenty billion, five hundred forty-two million, sixty-five thousand, six hundred four".