23531640 has 64 divisors (see below), whose sum is σ = 77016960. Its totient is φ = 5704320.

The previous prime is 23531617. The next prime is 23531647. The reversal of 23531640 is 4613532.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 23531640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23531647) 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, 7594 + ... + 10233.

It is an arithmetic number, because the mean of its divisors is an integer number (1203390).

Almost surely, 2^23531640 is an apocalyptic number.

23531640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23531640 is an abundant number, since it is smaller than the sum of its proper divisors (53485320).

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

23531640 is a wasteful number, since it uses less digits than its factorization.

23531640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17852 (or 17848 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 23531640 is about 4850.9421765261. The cubic root of 23531640 is about 286.5612075277.

It can be divided in two parts, 2353 and 1640, that added together give a palindrome (3993).

The spelling of 23531640 in words is "twenty-three million, five hundred thirty-one thousand, six hundred forty".