20643815996 has 12 divisors (see below), whose sum is σ = 37372425720. Its totient is φ = 9965980080.

The previous prime is 20643815977. The next prime is 20643816007. The reversal of 20643815996 is 69951834602.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 88981850 + ... + 88982081.

It is an arithmetic number, because the mean of its divisors is an integer number (3114368810).

Almost surely, 2^20643815996 is an apocalyptic number.

It is an amenable number.

20643815996 is a deficient number, since it is larger than the sum of its proper divisors (16728609724).

20643815996 is a wasteful number, since it uses less digits than its factorization.

20643815996 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 177963964 (or 177963962 counting only the distinct ones).

The product of its (nonzero) digits is 2799360, while the sum is 53.

The spelling of 20643815996 in words is "twenty billion, six hundred forty-three million, eight hundred fifteen thousand, nine hundred ninety-six".