21642601652 has 24 divisors (see below), whose sum is σ = 44168577600. Its totient is φ = 9275400120.

The previous prime is 21642601619. The next prime is 21642601699. The reversal of 21642601652 is 25610624612.

It is a congruent 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, 7885874 + ... + 7888617.

It is an arithmetic number, because the mean of its divisors is an integer number (1840357400).

Almost surely, 2^21642601652 is an apocalyptic number.

It is an amenable number.

21642601652 is an abundant number, since it is smaller than the sum of its proper divisors (22525975948).

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

21642601652 is a wasteful number, since it uses less digits than its factorization.

21642601652 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15774516 (or 15774500 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 35.

The spelling of 21642601652 in words is "twenty-one billion, six hundred forty-two million, six hundred one thousand, six hundred fifty-two".