23991657 has 4 divisors (see below), whose sum is σ = 31988880. Its totient is φ = 15994436.

The previous prime is 23991631. The next prime is 23991677. The reversal of 23991657 is 75619932.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 23991657 - 2¹⁶ = 23926121 is a prime.

It is not an unprimeable number, because it can be changed into a prime (23991677) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3998607 + ... + 3998612.

It is an arithmetic number, because the mean of its divisors is an integer number (7997220).

Almost surely, 2^23991657 is an apocalyptic number.

It is an amenable number.

23991657 is a deficient number, since it is larger than the sum of its proper divisors (7997223).

23991657 is an equidigital number, since it uses as much as digits as its factorization.

23991657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7997222.

The product of its digits is 102060, while the sum is 42.

The square root of 23991657 is about 4898.1279076806. The cubic root of 23991657 is about 288.4164860539.

The spelling of 23991657 in words is "twenty-three million, nine hundred ninety-one thousand, six hundred fifty-seven".