21664982275 has 48 divisors (see below), whose sum is σ = 28649237760. Its totient is φ = 16205616000.

The previous prime is 21664982249. The next prime is 21664982293. The reversal of 21664982275 is 57228946612.

It is a happy number.

It is not a de Polignac number, because 21664982275 - 2¹⁹ = 21664457987 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 22403842 + ... + 22404808.

It is an arithmetic number, because the mean of its divisors is an integer number (596859120).

Almost surely, 2^21664982275 is an apocalyptic number.

21664982275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21664982275 is a deficient number, since it is larger than the sum of its proper divisors (6984255485).

21664982275 is a wasteful number, since it uses less digits than its factorization.

21664982275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1564 (or 1559 counting only the distinct ones).

The product of its digits is 2903040, while the sum is 52.

The spelling of 21664982275 in words is "twenty-one billion, six hundred sixty-four million, nine hundred eighty-two thousand, two hundred seventy-five".