23684125721 has 2 divisors, whose sum is σ = 23684125722. Its totient is φ = 23684125720.

The previous prime is 23684125687. The next prime is 23684125757. The reversal of 23684125721 is 12752148632.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17943942025 + 5740183696 = 133955^2 + 75764^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23684125721 is a prime.

It is a super-2 number, since 2×23684125721² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (23684125021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11842062860 + 11842062861.

It is an arithmetic number, because the mean of its divisors is an integer number (11842062861).

Almost surely, 2^23684125721 is an apocalyptic number.

It is an amenable number.

23684125721 is a deficient number, since it is larger than the sum of its proper divisors (1).

23684125721 is an equidigital number, since it uses as much as digits as its factorization.

23684125721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 161280, while the sum is 41.

The spelling of 23684125721 in words is "twenty-three billion, six hundred eighty-four million, one hundred twenty-five thousand, seven hundred twenty-one".