23131861 has 2 divisors, whose sum is σ = 23131862. Its totient is φ = 23131860.

The previous prime is 23131853. The next prime is 23131877. The reversal of 23131861 is 16813132.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23097636 + 34225 = 4806^2 + 185^2 .

It is a cyclic number.

It is not a de Polignac number, because 23131861 - 2³ = 23131853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23131811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11565930 + 11565931.

It is an arithmetic number, because the mean of its divisors is an integer number (11565931).

Almost surely, 2^23131861 is an apocalyptic number.

It is an amenable number.

23131861 is a deficient number, since it is larger than the sum of its proper divisors (1).

23131861 is an equidigital number, since it uses as much as digits as its factorization.

23131861 is an evil number, because the sum of its binary digits is even.

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

The square root of 23131861 is about 4809.5593353238. The cubic root of 23131861 is about 284.9291339142.

Adding to 23131861 its reverse (16813132), we get a palindrome (39944993).

The spelling of 23131861 in words is "twenty-three million, one hundred thirty-one thousand, eight hundred sixty-one".