20815966919968 has 48 divisors (see below), whose sum is σ = 44775484399296. Its totient is φ = 9447313296640.

The previous prime is 20815966919927. The next prime is 20815966919983. The reversal of 20815966919968 is 86991966951802.

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 7 ways as a sum of consecutive naturals, for example, 45050596 + ... + 45510307.

It is an arithmetic number, because the mean of its divisors is an integer number (932822591652).

Almost surely, 2^{20815966919968} is an apocalyptic number.

It is an amenable number.

20815966919968 is an abundant number, since it is smaller than the sum of its proper divisors (23959517479328).

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

20815966919968 is a wasteful number, since it uses less digits than its factorization.

20815966919968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90561577 (or 90561569 counting only the distinct ones).

The product of its (nonzero) digits is 906992640, while the sum is 79.

The spelling of 20815966919968 in words is "twenty trillion, eight hundred fifteen billion, nine hundred sixty-six million, nine hundred nineteen thousand, nine hundred sixty-eight".