23978191 has 4 divisors (see below), whose sum is σ = 24315984. Its totient is φ = 23640400.

The previous prime is 23978179. The next prime is 23978233. The reversal of 23978191 is 19187932.

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

It is a cyclic number.

It is not a de Polignac number, because 23978191 - 2¹³ = 23969999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (23978111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 168790 + ... + 168931.

It is an arithmetic number, because the mean of its divisors is an integer number (6078996).

Almost surely, 2^23978191 is an apocalyptic number.

23978191 is a deficient number, since it is larger than the sum of its proper divisors (337793).

23978191 is an equidigital number, since it uses as much as digits as its factorization.

23978191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 337792.

The product of its digits is 27216, while the sum is 40.

The square root of 23978191 is about 4896.7531079277. The cubic root of 23978191 is about 288.3625153026.

The spelling of 23978191 in words is "twenty-three million, nine hundred seventy-eight thousand, one hundred ninety-one".