20615920331920 has 40 divisors (see below), whose sum is σ = 48035988859320. Its totient is φ = 8228480117760.

The previous prime is 20615920331893. The next prime is 20615920331939. The reversal of 20615920331920 is 2913302951602.

It can be written as a sum of positive squares in 4 ways, for example, as 80086736016 + 20535833595904 = 282996^2 + 4531648^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×20615920331920² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 279463125 + ... + 279536884.

It is an arithmetic number, because the mean of its divisors is an integer number (1200899721483).

Almost surely, 2^{20615920331920} is an apocalyptic number.

20615920331920 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20615920331920 is an abundant number, since it is smaller than the sum of its proper divisors (27420068527400).

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

20615920331920 is a wasteful number, since it uses less digits than its factorization.

20615920331920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 559000483 (or 559000477 counting only the distinct ones).

The product of its (nonzero) digits is 174960, while the sum is 43.

The spelling of 20615920331920 in words is "twenty trillion, six hundred fifteen billion, nine hundred twenty million, three hundred thirty-one thousand, nine hundred twenty".