231605440 has 112 divisors (see below), whose sum is σ = 633496320. Its totient is φ = 79764480.

The previous prime is 231605431. The next prime is 231605447. The reversal of 231605440 is 44506132.

It is not an unprimeable number, because it can be changed into a prime (231605447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65149 + ... + 68611.

Almost surely, 2^231605440 is an apocalyptic number.

231605440 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 231605440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (316748160).

231605440 is an abundant number, since it is smaller than the sum of its proper divisors (401890880).

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

231605440 is a wasteful number, since it uses less digits than its factorization.

231605440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3510 (or 3500 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 231605440 is about 15218.5886336414. The cubic root of 231605440 is about 614.1148303164.

The spelling of 231605440 in words is "two hundred thirty-one million, six hundred five thousand, four hundred forty".