21621361544624 has 20 divisors (see below), whose sum is σ = 41891460170040. Its totient is φ = 10810662145920.

The previous prime is 21621361544609. The next prime is 21621361544683. The reversal of 21621361544624 is 42644516312612.

It is a hoax number, since the sum of its digits (47) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17012564 + ... + 18239244.

It is an arithmetic number, because the mean of its divisors is an integer number (2094573008502).

Almost surely, 2^{21621361544624} is an apocalyptic number.

It is an amenable number.

21621361544624 is a deficient number, since it is larger than the sum of its proper divisors (20270098625416).

21621361544624 is a wasteful number, since it uses less digits than its factorization.

21621361544624 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2328308 (or 2328302 counting only the distinct ones).

The product of its digits is 1658880, while the sum is 47.

The spelling of 21621361544624 in words is "twenty-one trillion, six hundred twenty-one billion, three hundred sixty-one million, five hundred forty-four thousand, six hundred twenty-four".