231366640 has 80 divisors (see below), whose sum is σ = 574606080. Its totient is φ = 86446080.

The previous prime is 231366613. The next prime is 231366673. The reversal of 231366640 is 46663132.

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

It is a Harshad number since it is a multiple of its sum of digits (31).

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 15 ways as a sum of consecutive naturals, for example, 70312 + ... + 73528.

It is an arithmetic number, because the mean of its divisors is an integer number (7182576).

Almost surely, 2^231366640 is an apocalyptic number.

231366640 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 231366640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (287303040).

231366640 is an abundant number, since it is smaller than the sum of its proper divisors (343239440).

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

231366640 is a wasteful number, since it uses less digits than its factorization.

231366640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3290 (or 3284 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 31.

The square root of 231366640 is about 15210.7409418476. The cubic root of 231366640 is about 613.9036938646.

The spelling of 231366640 in words is "two hundred thirty-one million, three hundred sixty-six thousand, six hundred forty".