231528240 has 160 divisors (see below), whose sum is σ = 819322560. Its totient is φ = 60051456.

The previous prime is 231528217. The next prime is 231528247. The reversal of 231528240 is 42825132.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (231528247) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 78472 + ... + 81368.

It is an arithmetic number, because the mean of its divisors is an integer number (5120766).

Almost surely, 2^231528240 is an apocalyptic number.

231528240 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 231528240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (409661280).

231528240 is an abundant number, since it is smaller than the sum of its proper divisors (587794320).

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

231528240 is a wasteful number, since it uses less digits than its factorization.

231528240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2956 (or 2944 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 231528240 is about 15216.0520503842. The cubic root of 231528240 is about 614.0465893552.

The spelling of 231528240 in words is "two hundred thirty-one million, five hundred twenty-eight thousand, two hundred forty".