231122813 has 2 divisors, whose sum is σ = 231122814. Its totient is φ = 231122812.

The previous prime is 231122809. The next prime is 231122819. The reversal of 231122813 is 318221132.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 150356644 + 80766169 = 12262^2 + 8987^2 .

It is a cyclic number.

It is not a de Polignac number, because 231122813 - 2² = 231122809 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231122819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115561406 + 115561407.

It is an arithmetic number, because the mean of its divisors is an integer number (115561407).

Almost surely, 2^231122813 is an apocalyptic number.

It is an amenable number.

231122813 is a deficient number, since it is larger than the sum of its proper divisors (1).

231122813 is an equidigital number, since it uses as much as digits as its factorization.

231122813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 576, while the sum is 23.

The square root of 231122813 is about 15202.7238677811. The cubic root of 231122813 is about 613.6879628077.

Adding to 231122813 its reverse (318221132), we get a palindrome (549343945).

The spelling of 231122813 in words is "two hundred thirty-one million, one hundred twenty-two thousand, eight hundred thirteen".