23712781 has 2 divisors, whose sum is σ = 23712782. Its totient is φ = 23712780.

The previous prime is 23712761. The next prime is 23712811. The reversal of 23712781 is 18721732.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14891881 + 8820900 = 3859^2 + 2970^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23712781 is a prime.

It is a super-2 number, since 2×23712781² = 1124591965507922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23712761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11856390 + 11856391.

It is an arithmetic number, because the mean of its divisors is an integer number (11856391).

Almost surely, 2^23712781 is an apocalyptic number.

It is an amenable number.

23712781 is a deficient number, since it is larger than the sum of its proper divisors (1).

23712781 is an equidigital number, since it uses as much as digits as its factorization.

23712781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4704, while the sum is 31.

The square root of 23712781 is about 4869.5770863598. The cubic root of 23712781 is about 287.2946223200.

The spelling of 23712781 in words is "twenty-three million, seven hundred twelve thousand, seven hundred eighty-one".