21137156272 has 10 divisors (see below), whose sum is σ = 40953240308. Its totient is φ = 10568578128.

The previous prime is 21137156269. The next prime is 21137156279. The reversal of 21137156272 is 27265173112.

It is not an unprimeable number, because it can be changed into a prime (21137156279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660536118 + ... + 660536149.

Almost surely, 2^21137156272 is an apocalyptic number.

It is an amenable number.

21137156272 is a deficient number, since it is larger than the sum of its proper divisors (19816084036).

21137156272 is a wasteful number, since it uses less digits than its factorization.

21137156272 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1321072275 (or 1321072269 counting only the distinct ones).

The product of its digits is 35280, while the sum is 37.

The spelling of 21137156272 in words is "twenty-one billion, one hundred thirty-seven million, one hundred fifty-six thousand, two hundred seventy-two".