231324640 has 48 divisors (see below), whose sum is σ = 553452480. Its totient is φ = 91353600.

The previous prime is 231324607. The next prime is 231324641. The reversal of 231324640 is 46423132.

It is a super-2 number, since 2×231324640² = 107022178142259200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231324641) 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, 3490 + ... + 21790.

It is an arithmetic number, because the mean of its divisors is an integer number (11530260).

Almost surely, 2^231324640 is an apocalyptic number.

231324640 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 231324640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (276726240).

231324640 is an abundant number, since it is smaller than the sum of its proper divisors (322127840).

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

231324640 is a wasteful number, since it uses less digits than its factorization.

231324640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18395 (or 18387 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 25.

The square root of 231324640 is about 15209.3602758301. The cubic root of 231324640 is about 613.8665442919.

Adding to 231324640 its reverse (46423132), we get a palindrome (277747772).

It can be divided in two parts, 23132 and 4640, that added together give a palindrome (27772).

The spelling of 231324640 in words is "two hundred thirty-one million, three hundred twenty-four thousand, six hundred forty".