231643613 has 2 divisors, whose sum is σ = 231643614. Its totient is φ = 231643612.

The previous prime is 231643597. The next prime is 231643627. The reversal of 231643613 is 316346132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 228674884 + 2968729 = 15122^2 + 1723^2 .

It is a cyclic number.

It is not a de Polignac number, because 231643613 - 2⁴ = 231643597 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231643693) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115821806 + 115821807.

It is an arithmetic number, because the mean of its divisors is an integer number (115821807).

Almost surely, 2^231643613 is an apocalyptic number.

It is an amenable number.

231643613 is a deficient number, since it is larger than the sum of its proper divisors (1).

231643613 is an equidigital number, since it uses as much as digits as its factorization.

231643613 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7776, while the sum is 29.

The square root of 231643613 is about 15219.8427390036. The cubic root of 231643613 is about 614.1485677473.

Adding to 231643613 its reverse (316346132), we get a palindrome (547989745).

The spelling of 231643613 in words is "two hundred thirty-one million, six hundred forty-three thousand, six hundred thirteen".