23891639 has 2 divisors, whose sum is σ = 23891640. Its totient is φ = 23891638.

The previous prime is 23891627. The next prime is 23891657. The reversal of 23891639 is 93619832.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 23891639 - 2²⁴ = 7114423 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 23891596 and 23891605.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23891689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11945819 + 11945820.

It is an arithmetic number, because the mean of its divisors is an integer number (11945820).

Almost surely, 2^23891639 is an apocalyptic number.

23891639 is a deficient number, since it is larger than the sum of its proper divisors (1).

23891639 is an equidigital number, since it uses as much as digits as its factorization.

23891639 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69984, while the sum is 41.

The square root of 23891639 is about 4887.9074254736. The cubic root of 23891639 is about 288.0151379324.

The spelling of 23891639 in words is "twenty-three million, eight hundred ninety-one thousand, six hundred thirty-nine".