231718032540 has 36 divisors (see below), whose sum is σ = 702878032584. Its totient is φ = 61791475296.

The previous prime is 231718032527. The next prime is 231718032593. The reversal of 231718032540 is 45230817132.

231718032540 is a `hidden beast` number, since 2 + 3 + 1 + 7 + 1 + 80 + 32 + 540 = 666.

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

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

It is a junction number, because it is equal to n+sod(n) for n = 231718032495 and 231718032504.

It is a congruent number.

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, 643661022 + ... + 643661381.

It is an arithmetic number, because the mean of its divisors is an integer number (19524389794).

Almost surely, 2^231718032540 is an apocalyptic number.

231718032540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231718032540 is an abundant number, since it is smaller than the sum of its proper divisors (471160000044).

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

231718032540 is a wasteful number, since it uses less digits than its factorization.

231718032540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1287322418 (or 1287322413 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

Adding to 231718032540 its reverse (45230817132), we get a palindrome (276948849672).

The spelling of 231718032540 in words is "two hundred thirty-one billion, seven hundred eighteen million, thirty-two thousand, five hundred forty".