23187440 has 20 divisors (see below), whose sum is σ = 53910984. Its totient is φ = 9274944.

The previous prime is 23187433. The next prime is 23187457. The reversal of 23187440 is 4478132.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 144842 + ... + 145001.

Almost surely, 2^23187440 is an apocalyptic number.

23187440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

23187440 is an abundant number, since it is smaller than the sum of its proper divisors (30723544).

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

23187440 is a wasteful number, since it uses less digits than its factorization.

23187440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 289856 (or 289850 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 23187440 is about 4815.3338409709. Note that the first 3 decimals coincide. The cubic root of 23187440 is about 285.1571514540.

The spelling of 23187440 in words is "twenty-three million, one hundred eighty-seven thousand, four hundred forty".