23297991 has 16 divisors (see below), whose sum is σ = 32283360. Its totient is φ = 14927360.

The previous prime is 23297983. The next prime is 23297999. The reversal of 23297991 is 19979232.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (23297983) and next prime (23297999).

It is a cyclic number.

It is not a de Polignac number, because 23297991 - 2³ = 23297983 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23297999) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23971 + ... + 24923.

It is an arithmetic number, because the mean of its divisors is an integer number (2017710).

Almost surely, 2^23297991 is an apocalyptic number.

23297991 is a deficient number, since it is larger than the sum of its proper divisors (8985369).

23297991 is a wasteful number, since it uses less digits than its factorization.

23297991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1266.

The product of its digits is 61236, while the sum is 42.

The square root of 23297991 is about 4826.7992500207. The cubic root of 23297991 is about 285.6096153853.

The spelling of 23297991 in words is "twenty-three million, two hundred ninety-seven thousand, nine hundred ninety-one".