20718315738828 has 36 divisors (see below), whose sum is σ = 54310975828200. Its totient is φ = 6906105245952.

The previous prime is 20718315738811. The next prime is 20718315738847. The reversal of 20718315738828 is 82883751381702.

20718315738828 is a `hidden beast` number, since 2 + 0 + 7 + 1 + 8 + 31 + 573 + 8 + 8 + 28 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10657568853 + ... + 10657570796.

It is an arithmetic number, because the mean of its divisors is an integer number (1508638217450).

Almost surely, 2^{20718315738828} is an apocalyptic number.

It is an amenable number.

20718315738828 is an abundant number, since it is smaller than the sum of its proper divisors (33592660089372).

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

20718315738828 is a wasteful number, since it uses less digits than its factorization.

20718315738828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21315139668 (or 21315139654 counting only the distinct ones).

The product of its (nonzero) digits is 36126720, while the sum is 63.

The spelling of 20718315738828 in words is "twenty trillion, seven hundred eighteen billion, three hundred fifteen million, seven hundred thirty-eight thousand, eight hundred twenty-eight".