23698721 has 2 divisors, whose sum is σ = 23698722. Its totient is φ = 23698720.

The previous prime is 23698691. The next prime is 23698723. The reversal of 23698721 is 12789632.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21022225 + 2676496 = 4585^2 + 1636^2 .

It is a cyclic number.

It is not a de Polignac number, because 23698721 - 2¹⁰ = 23697697 is a prime.

Together with 23698723, it forms a pair of twin primes.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is not a weakly prime, because it can be changed into another prime (23698723) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11849360 + 11849361.

It is an arithmetic number, because the mean of its divisors is an integer number (11849361).

Almost surely, 2^23698721 is an apocalyptic number.

It is an amenable number.

23698721 is a deficient number, since it is larger than the sum of its proper divisors (1).

23698721 is an equidigital number, since it uses as much as digits as its factorization.

23698721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 38.

The square root of 23698721 is about 4868.1332151041. The cubic root of 23698721 is about 287.2378293047.

The spelling of 23698721 in words is "twenty-three million, six hundred ninety-eight thousand, seven hundred twenty-one".