231612131520 has 1344 divisors, whose sum is σ = 1030340653056. Its totient is φ = 46363484160.

The previous prime is 231612131489. The next prime is 231612131533. The reversal of 231612131520 is 25131216132.

231612131520 is a `hidden beast` number, since 2 + 3 + 1 + 6 + 1 + 2 + 131 + 520 = 666.

It is a tau number, because it is divible by the number of its divisors (1344).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 1020317647 + ... + 1020317873.

Almost surely, 2^231612131520 is an apocalyptic number.

231612131520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 231612131520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (515170326528).

231612131520 is an abundant number, since it is smaller than the sum of its proper divisors (798728521536).

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

231612131520 is a wasteful number, since it uses less digits than its factorization.

231612131520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418 (or 405 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

Adding to 231612131520 its reverse (25131216132), we get a palindrome (256743347652).

The spelling of 231612131520 in words is "two hundred thirty-one billion, six hundred twelve million, one hundred thirty-one thousand, five hundred twenty".