20731881157124 has 12 divisors (see below), whose sum is σ = 36280825389900. Its totient is φ = 10365931045728.

The previous prime is 20731881157123. The next prime is 20731881157133. The reversal of 20731881157124 is 42175118813702.

It can be written as a sum of positive squares in 2 ways, for example, as 4723624092100 + 16008257065024 = 2173390^2 + 4001032^2 .

It is a super-2 number, since 2×20731881157124² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20731881157123) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5169722 + ... + 8257710.

It is an arithmetic number, because the mean of its divisors is an integer number (3023402115825).

Almost surely, 2^{20731881157124} is an apocalyptic number.

It is an amenable number.

20731881157124 is a deficient number, since it is larger than the sum of its proper divisors (15548944232776).

20731881157124 is a wasteful number, since it uses less digits than its factorization.

20731881157124 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4766422 (or 4766420 counting only the distinct ones).

The product of its (nonzero) digits is 752640, while the sum is 50.

The spelling of 20731881157124 in words is "twenty trillion, seven hundred thirty-one billion, eight hundred eighty-one million, one hundred fifty-seven thousand, one hundred twenty-four".