21665564034004 has 48 divisors (see below), whose sum is σ = 42326218368000. Its totient is φ = 9619136091360.

The previous prime is 21665564033987. The next prime is 21665564034013. The reversal of 21665564034004 is 40043046556612.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9465642 + ... + 11529505.

It is an arithmetic number, because the mean of its divisors is an integer number (881796216000).

Almost surely, 2^{21665564034004} is an apocalyptic number.

It is an amenable number.

21665564034004 is a deficient number, since it is larger than the sum of its proper divisors (20660654333996).

21665564034004 is a wasteful number, since it uses less digits than its factorization.

21665564034004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20995708 (or 20995706 counting only the distinct ones).

The product of its (nonzero) digits is 2073600, while the sum is 46.

The spelling of 21665564034004 in words is "twenty-one trillion, six hundred sixty-five billion, five hundred sixty-four million, thirty-four thousand, four".