231391944 has 128 divisors (see below), whose sum is σ = 751872000. Its totient is φ = 64556352.

The previous prime is 231391939. The next prime is 231391991. The reversal of 231391944 is 449193132.

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

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

It is a junction number, because it is equal to n+sod(n) for n = 231391899 and 231391908.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 63237 + ... + 66795.

It is an arithmetic number, because the mean of its divisors is an integer number (5874000).

Almost surely, 2^231391944 is an apocalyptic number.

231391944 is a gapful number since it is divisible by the number (24) 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 231391944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (375936000).

231391944 is an abundant number, since it is smaller than the sum of its proper divisors (520480056).

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

231391944 is a wasteful number, since it uses less digits than its factorization.

231391944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3624 (or 3614 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 231391944 is about 15211.5726997572. The cubic root of 231391944 is about 613.9260734275.

The spelling of 231391944 in words is "two hundred thirty-one million, three hundred ninety-one thousand, nine hundred forty-four".