21576913137 has 32 divisors (see below), whose sum is σ = 34552828800. Its totient is φ = 13228681536.

The previous prime is 21576913129. The next prime is 21576913139. The reversal of 21576913137 is 73131967512.

It is not a de Polignac number, because 21576913137 - 2³ = 21576913129 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21576913092 and 21576913101.

It is not an unprimeable number, because it can be changed into a prime (21576913139) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19843 + ... + 208680.

It is an arithmetic number, because the mean of its divisors is an integer number (1079775900).

Almost surely, 2^21576913137 is an apocalyptic number.

21576913137 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

21576913137 is a deficient number, since it is larger than the sum of its proper divisors (12975915663).

21576913137 is a wasteful number, since it uses less digits than its factorization.

21576913137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228814 (or 228808 counting only the distinct ones).

The product of its digits is 238140, while the sum is 45.

The spelling of 21576913137 in words is "twenty-one billion, five hundred seventy-six million, nine hundred thirteen thousand, one hundred thirty-seven".