23161381 has 2 divisors, whose sum is σ = 23161382. Its totient is φ = 23161380.

The previous prime is 23161379. The next prime is 23161387. The reversal of 23161381 is 18316132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23136100 + 25281 = 4810^2 + 159^2 .

It is a cyclic number.

It is not a de Polignac number, because 23161381 - 2¹ = 23161379 is a prime.

It is a super-2 number, since 2×23161381² = 1072899139654322, which contains 22 as substring.

Together with 23161379, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23161387) 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, 11580690 + 11580691.

It is an arithmetic number, because the mean of its divisors is an integer number (11580691).

Almost surely, 2^23161381 is an apocalyptic number.

It is an amenable number.

23161381 is a deficient number, since it is larger than the sum of its proper divisors (1).

23161381 is an equidigital number, since it uses as much as digits as its factorization.

23161381 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 864, while the sum is 25.

The square root of 23161381 is about 4812.6272450710. The cubic root of 23161381 is about 285.0502876278.

The spelling of 23161381 in words is "twenty-three million, one hundred sixty-one thousand, three hundred eighty-one".