231525440 has 56 divisors (see below), whose sum is σ = 560710080. Its totient is φ = 91033088.

The previous prime is 231525433. The next prime is 231525443. The reversal of 231525440 is 44525132.

It is a happy number.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (231525443) 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, 12749 + ... + 25011.

It is an arithmetic number, because the mean of its divisors is an integer number (10012680).

Almost surely, 2^231525440 is an apocalyptic number.

231525440 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 231525440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (280355040).

231525440 is an abundant number, since it is smaller than the sum of its proper divisors (329184640).

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

231525440 is a wasteful number, since it uses less digits than its factorization.

231525440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12339 (or 12329 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 26.

The square root of 231525440 is about 15215.9600420085. The cubic root of 231525440 is about 614.0441140094.

The spelling of 231525440 in words is "two hundred thirty-one million, five hundred twenty-five thousand, four hundred forty".