231907840 has 80 divisors (see below), whose sum is σ = 560546712. Its totient is φ = 92012544.

The previous prime is 231907811. The next prime is 231907843. The reversal of 231907840 is 48709132.

It can be written as a sum of positive squares in 4 ways, for example, as 220938496 + 10969344 = 14864^2 + 3312^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 231907796 and 231907805.

It is not an unprimeable number, because it can be changed into a prime (231907843) 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, 401632 + ... + 402208.

Almost surely, 2^231907840 is an apocalyptic number.

231907840 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 231907840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (280273356).

231907840 is an abundant number, since it is smaller than the sum of its proper divisors (328638872).

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

231907840 is an equidigital number, since it uses as much as digits as its factorization.

231907840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 757 (or 741 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 231907840 is about 15228.5206110114. The cubic root of 231907840 is about 614.3819909363.

The spelling of 231907840 in words is "two hundred thirty-one million, nine hundred seven thousand, eight hundred forty".