23399921 has 2 divisors, whose sum is σ = 23399922. Its totient is φ = 23399920.

The previous prime is 23399911. The next prime is 23399953. The reversal of 23399921 is 12999332.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22429696 + 970225 = 4736^2 + 985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23399921 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (23399911) 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 as a sum of consecutive naturals, namely, 11699960 + 11699961.

It is an arithmetic number, because the mean of its divisors is an integer number (11699961).

Almost surely, 2^23399921 is an apocalyptic number.

It is an amenable number.

23399921 is a deficient number, since it is larger than the sum of its proper divisors (1).

23399921 is an equidigital number, since it uses as much as digits as its factorization.

23399921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 26244, while the sum is 38.

The square root of 23399921 is about 4837.3464833522. The cubic root of 23399921 is about 286.0255287170.

The spelling of 23399921 in words is "twenty-three million, three hundred ninety-nine thousand, nine hundred twenty-one".