18126731520 has 108 divisors (see below), whose sum is σ = 62716642716. Its totient is φ = 4833792000.

The previous prime is 18126731479. The next prime is 18126731521. The reversal of 18126731520 is 2513762181.

18126731520 is a `hidden beast` number, since 1 + 8 + 126 + 7 + 3 + 1 + 520 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 7456667904 + 10670063616 = 86352^2 + 103296^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (18126731521) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 775231 + ... + 798270.

Almost surely, 2^18126731520 is an apocalyptic number.

18126731520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18126731520 is an abundant number, since it is smaller than the sum of its proper divisors (44589911196).

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

18126731520 is a wasteful number, since it uses less digits than its factorization.

18126731520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1573528 (or 1573511 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The spelling of 18126731520 in words is "eighteen billion, one hundred twenty-six million, seven hundred thirty-one thousand, five hundred twenty".