23785256981 has 2 divisors, whose sum is σ = 23785256982. Its totient is φ = 23785256980.

The previous prime is 23785256939. The next prime is 23785256983. The reversal of 23785256981 is 18965258732.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23659054225 + 126202756 = 153815^2 + 11234^2 .

It is a cyclic number.

It is not a de Polignac number, because 23785256981 - 2²² = 23781062677 is a prime.

It is a super-2 number, since 2×23785256981² (a number of 22 digits) contains 22 as substring.

Together with 23785256983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23785256983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11892628490 + 11892628491.

It is an arithmetic number, because the mean of its divisors is an integer number (11892628491).

Almost surely, 2^23785256981 is an apocalyptic number.

It is an amenable number.

23785256981 is a deficient number, since it is larger than the sum of its proper divisors (1).

23785256981 is an equidigital number, since it uses as much as digits as its factorization.

23785256981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7257600, while the sum is 56.

The spelling of 23785256981 in words is "twenty-three billion, seven hundred eighty-five million, two hundred fifty-six thousand, nine hundred eighty-one".