21365025437564 has 12 divisors (see below), whose sum is σ = 38300716333488. Its totient is φ = 10421963628000.

The previous prime is 21365025437563. The next prime is 21365025437597. The reversal of 21365025437564 is 46573452056312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21365025437563) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 65137272512 + ... + 65137272839.

It is an arithmetic number, because the mean of its divisors is an integer number (3191726361124).

Almost surely, 2^{21365025437564} is an apocalyptic number.

It is an amenable number.

21365025437564 is a deficient number, since it is larger than the sum of its proper divisors (16935690895924).

21365025437564 is a wasteful number, since it uses less digits than its factorization.

21365025437564 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130274545396 (or 130274545394 counting only the distinct ones).

The product of its (nonzero) digits is 18144000, while the sum is 53.

The spelling of 21365025437564 in words is "twenty-one trillion, three hundred sixty-five billion, twenty-five million, four hundred thirty-seven thousand, five hundred sixty-four".