231532240 has 20 divisors (see below), whose sum is σ = 538312644. Its totient is φ = 92612864.

The previous prime is 231532229. The next prime is 231532243. The reversal of 231532240 is 42235132.

It can be written as a sum of positive squares in 2 ways, for example, as 64192144 + 167340096 = 8012^2 + 12936^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231532243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1446997 + ... + 1447156.

Almost surely, 2^231532240 is an apocalyptic number.

231532240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

231532240 is an abundant number, since it is smaller than the sum of its proper divisors (306780404).

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

231532240 is a wasteful number, since it uses less digits than its factorization.

231532240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2894166 (or 2894160 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 231532240 is about 15216.1834899557. The cubic root of 231532240 is about 614.0501255289.

Adding to 231532240 its reverse (42235132), we get a palindrome (273767372).

The spelling of 231532240 in words is "two hundred thirty-one million, five hundred thirty-two thousand, two hundred forty".