21654908504 has 8 divisors (see below), whose sum is σ = 40602953460. Its totient is φ = 10827454248.

The previous prime is 21654908491. The next prime is 21654908573. The reversal of 21654908504 is 40580945612.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21654908504² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1353431774 + ... + 1353431789.

Almost surely, 2^21654908504 is an apocalyptic number.

It is an amenable number.

21654908504 is a deficient number, since it is larger than the sum of its proper divisors (18948044956).

21654908504 is a wasteful number, since it uses less digits than its factorization.

21654908504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2706863569 (or 2706863565 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 44.

The spelling of 21654908504 in words is "twenty-one billion, six hundred fifty-four million, nine hundred eight thousand, five hundred four".