21353566272 has 28 divisors (see below), whose sum is σ = 56497977936. Its totient is φ = 7117855360.

The previous prime is 21353566237. The next prime is 21353566301. The reversal of 21353566272 is 27266535312.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55608054 + ... + 55608437.

Almost surely, 2^21353566272 is an apocalyptic number.

It is an amenable number.

21353566272 is an abundant number, since it is smaller than the sum of its proper divisors (35144411664).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21353566272 is a wasteful number, since it uses less digits than its factorization.

21353566272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111216506 (or 111216496 counting only the distinct ones).

The product of its digits is 453600, while the sum is 42.

The spelling of 21353566272 in words is "twenty-one billion, three hundred fifty-three million, five hundred sixty-six thousand, two hundred seventy-two".