23071981 has 2 divisors, whose sum is σ = 23071982. Its totient is φ = 23071980.

The previous prime is 23071949. The next prime is 23071999. The reversal of 23071981 is 18917032.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21206025 + 1865956 = 4605^2 + 1366^2 .

It is a cyclic number.

It is not a de Polignac number, because 23071981 - 2⁵ = 23071949 is a prime.

It is a super-2 number, since 2×23071981² = 1064632614528722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23071901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11535990 + 11535991.

It is an arithmetic number, because the mean of its divisors is an integer number (11535991).

Almost surely, 2^23071981 is an apocalyptic number.

It is an amenable number.

23071981 is a deficient number, since it is larger than the sum of its proper divisors (1).

23071981 is an equidigital number, since it uses as much as digits as its factorization.

23071981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 23071981 is about 4803.3301989349. The cubic root of 23071981 is about 284.6830620596.

The spelling of 23071981 in words is "twenty-three million, seventy-one thousand, nine hundred eighty-one".