21536403272 has 16 divisors (see below), whose sum is σ = 40797054060. Its totient is φ = 10657188864.

The previous prime is 21536403263. The next prime is 21536403283. The reversal of 21536403272 is 27230463512.

It can be written as a sum of positive squares in 2 ways, for example, as 20567575396 + 968827876 = 143414^2 + 31126^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13875773 + ... + 13877324.

Almost surely, 2^21536403272 is an apocalyptic number.

It is an amenable number.

21536403272 is a deficient number, since it is larger than the sum of its proper divisors (19260650788).

21536403272 is a wasteful number, since it uses less digits than its factorization.

21536403272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27753200 (or 27753196 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 35.

Adding to 21536403272 its reverse (27230463512), we get a palindrome (48766866784).

The spelling of 21536403272 in words is "twenty-one billion, five hundred thirty-six million, four hundred three thousand, two hundred seventy-two".