231312144 has 60 divisors (see below), whose sum is σ = 695123664. Its totient is φ = 66088512.

The previous prime is 231312143. The next prime is 231312161. The reversal of 231312144 is 441213132.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 231312144.

It is not an unprimeable number, because it can be changed into a prime (231312143) 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, 46822 + ... + 51525.

Almost surely, 2^231312144 is an apocalyptic number.

231312144 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

231312144 is an abundant number, since it is smaller than the sum of its proper divisors (463811520).

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

231312144 is a wasteful number, since it uses less digits than its factorization.

231312144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98372 (or 98359 counting only the distinct ones).

The product of its digits is 576, while the sum is 21.

The square root of 231312144 is about 15208.9494706242. The cubic root of 231312144 is about 613.8554905415.

Adding to 231312144 its reverse (441213132), we get a palindrome (672525276).

The spelling of 231312144 in words is "two hundred thirty-one million, three hundred twelve thousand, one hundred forty-four".