23979721 has 2 divisors, whose sum is σ = 23979722. Its totient is φ = 23979720.

The previous prime is 23979719. The next prime is 23979733. The reversal of 23979721 is 12797932.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 22429696 + 1550025 = 4736^2 + 1245^2 .

It is a cyclic number.

It is not a de Polignac number, because 23979721 - 2¹ = 23979719 is a prime.

Together with 23979719, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (23979421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11989860 + 11989861.

It is an arithmetic number, because the mean of its divisors is an integer number (11989861).

Almost surely, 2^23979721 is an apocalyptic number.

It is an amenable number.

23979721 is a deficient number, since it is larger than the sum of its proper divisors (1).

23979721 is an equidigital number, since it uses as much as digits as its factorization.

23979721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47628, while the sum is 40.

The square root of 23979721 is about 4896.9093314049. The cubic root of 23979721 is about 288.3686484490.

The spelling of 23979721 in words is "twenty-three million, nine hundred seventy-nine thousand, seven hundred twenty-one".