21660535036164 has 12 divisors (see below), whose sum is σ = 50541248417744. Its totient is φ = 7220178345384.

The previous prime is 21660535036123. The next prime is 21660535036177. The reversal of 21660535036164 is 46163053506612.

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

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 3 ways as a sum of consecutive naturals, for example, 902522293162 + ... + 902522293185.

Almost surely, 2^{21660535036164} is an apocalyptic number.

It is an amenable number.

21660535036164 is an abundant number, since it is smaller than the sum of its proper divisors (28880713381580).

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

21660535036164 is a wasteful number, since it uses less digits than its factorization.

21660535036164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1805044586354 (or 1805044586352 counting only the distinct ones).

The product of its (nonzero) digits is 2332800, while the sum is 48.

The spelling of 21660535036164 in words is "twenty-one trillion, six hundred sixty billion, five hundred thirty-five million, thirty-six thousand, one hundred sixty-four".