20972832399 has 24 divisors (see below), whose sum is σ = 30628804752. Its totient is φ = 13827617280.

The previous prime is 20972832337. The next prime is 20972832403. The reversal of 20972832399 is 99323827902.

It is a happy number.

20972832399 is a `hidden beast` number, since 209 + 7 + 28 + 323 + 99 = 666.

It is a Cunningham number, because it is equal to 144820²-1.

It is not a de Polignac number, because 20972832399 - 2⁷ = 20972832271 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20972836399) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1295344 + ... + 1311434.

It is an arithmetic number, because the mean of its divisors is an integer number (1276200198).

Almost surely, 2^20972832399 is an apocalyptic number.

20972832399 is a deficient number, since it is larger than the sum of its proper divisors (9655972353).

20972832399 is a wasteful number, since it uses less digits than its factorization.

20972832399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17687 (or 17684 counting only the distinct ones).

The product of its (nonzero) digits is 2939328, while the sum is 54.

The spelling of 20972832399 in words is "twenty billion, nine hundred seventy-two million, eight hundred thirty-two thousand, three hundred ninety-nine".