18500131384 has 32 divisors (see below), whose sum is σ = 40006850400. Its totient is φ = 7855885440.

The previous prime is 18500131381. The next prime is 18500131409. The reversal of 18500131384 is 48313100581.

It is a happy number.

It is a super-2 number, since 2×18500131384² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18500131381) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1509307 + ... + 1521514.

It is an arithmetic number, because the mean of its divisors is an integer number (1250214075).

Almost surely, 2^18500131384 is an apocalyptic number.

18500131384 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

18500131384 is an abundant number, since it is smaller than the sum of its proper divisors (21506719016).

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

18500131384 is a wasteful number, since it uses less digits than its factorization.

18500131384 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3030943 (or 3030939 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 34.

The spelling of 18500131384 in words is "eighteen billion, five hundred million, one hundred thirty-one thousand, three hundred eighty-four".