20974924999 has 32 divisors (see below), whose sum is σ = 25471846400. Its totient is φ = 16871626080.

The previous prime is 20974924991. The next prime is 20974925021. The reversal of 20974924999 is 99942947902.

It is not a de Polignac number, because 20974924999 - 2³ = 20974924991 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20974924999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20974924991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10555084 + ... + 10557070.

It is an arithmetic number, because the mean of its divisors is an integer number (795995200).

Almost surely, 2^20974924999 is an apocalyptic number.

20974924999 is a deficient number, since it is larger than the sum of its proper divisors (4496921401).

20974924999 is a wasteful number, since it uses less digits than its factorization.

20974924999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2723.

The product of its (nonzero) digits is 26453952, while the sum is 64.

The spelling of 20974924999 in words is "twenty billion, nine hundred seventy-four million, nine hundred twenty-four thousand, nine hundred ninety-nine".