20972623815 has 128 divisors (see below), whose sum is σ = 44142658560. Its totient is φ = 9313574400.

The previous prime is 20972623811. The next prime is 20972623873. The reversal of 20972623815 is 51832627902.

20972623815 is a `hidden beast` number, since 2 + 0 + 9 + 7 + 2 + 623 + 8 + 15 = 666.

It is not a de Polignac number, because 20972623815 - 2² = 20972623811 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20972623811) by changing a digit.

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 127 ways as a sum of consecutive naturals, for example, 2524809 + ... + 2533101.

It is an arithmetic number, because the mean of its divisors is an integer number (344864520).

Almost surely, 2^20972623815 is an apocalyptic number.

20972623815 is an abundant number, since it is smaller than the sum of its proper divisors (23170034745).

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

20972623815 is a wasteful number, since it uses less digits than its factorization.

20972623815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8462 (or 8456 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The spelling of 20972623815 in words is "twenty billion, nine hundred seventy-two million, six hundred twenty-three thousand, eight hundred fifteen".