23566640 has 40 divisors (see below), whose sum is σ = 55079808. Its totient is φ = 9377280.

The previous prime is 23566637. The next prime is 23566657. The reversal of 23566640 is 4666532.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 23566597 and 23566606.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17180 + ... + 18500.

Almost surely, 2^23566640 is an apocalyptic number.

23566640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23566640 is an abundant number, since it is smaller than the sum of its proper divisors (31513168).

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

23566640 is a wasteful number, since it uses less digits than its factorization.

23566640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1557 (or 1551 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 32.

The square root of 23566640 is about 4854.5483827026. The cubic root of 23566640 is about 286.7032102923.

The spelling of 23566640 in words is "twenty-three million, five hundred sixty-six thousand, six hundred forty".