231668640 has 384 divisors, whose sum is σ = 952197120. Its totient is φ = 51508224.

The previous prime is 231668629. The next prime is 231668681. The reversal of 231668640 is 46866132.

231668640 is a `hidden beast` number, since 2 + 3 + 1 + 6 + 6 + 8 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 231668595 and 231668604.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1421199 + ... + 1421361.

It is an arithmetic number, because the mean of its divisors is an integer number (2479680).

Almost surely, 2^231668640 is an apocalyptic number.

231668640 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 231668640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (476098560).

231668640 is an abundant number, since it is smaller than the sum of its proper divisors (720528480).

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

231668640 is a wasteful number, since it uses less digits than its factorization.

231668640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 241 (or 227 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 36.

The square root of 231668640 is about 15220.6649000627. The cubic root of 231668640 is about 614.1706846859.

The spelling of 231668640 in words is "two hundred thirty-one million, six hundred sixty-eight thousand, six hundred forty".