23721965 has 4 divisors (see below), whose sum is σ = 28466364. Its totient is φ = 18977568.

The previous prime is 23721959. The next prime is 23721979. The reversal of 23721965 is 56912732.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10201636 + 13520329 = 3194^2 + 3677^2 .

It is a cyclic number.

It is not a de Polignac number, because 23721965 - 2¹⁰ = 23720941 is a prime.

It is a super-2 number, since 2×23721965² = 1125463246922450, which contains 22 as substring.

It is a Duffinian number.

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, 2372192 + ... + 2372201.

It is an arithmetic number, because the mean of its divisors is an integer number (7116591).

Almost surely, 2^23721965 is an apocalyptic number.

It is an amenable number.

23721965 is a deficient number, since it is larger than the sum of its proper divisors (4744399).

23721965 is an equidigital number, since it uses as much as digits as its factorization.

23721965 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4744398.

The product of its digits is 22680, while the sum is 35.

The square root of 23721965 is about 4870.5199927728. The cubic root of 23721965 is about 287.3317074297.

The spelling of 23721965 in words is "twenty-three million, seven hundred twenty-one thousand, nine hundred sixty-five".