231976517 has 2 divisors, whose sum is σ = 231976518. Its totient is φ = 231976516.

The previous prime is 231976513. The next prime is 231976519. The reversal of 231976517 is 715679132.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 209641441 + 22335076 = 14479^2 + 4726^2 .

It is a cyclic number.

It is not a de Polignac number, because 231976517 - 2² = 231976513 is a prime.

Together with 231976519, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (231976513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115988258 + 115988259.

It is an arithmetic number, because the mean of its divisors is an integer number (115988259).

Almost surely, 2^231976517 is an apocalyptic number.

It is an amenable number.

231976517 is a deficient number, since it is larger than the sum of its proper divisors (1).

231976517 is an equidigital number, since it uses as much as digits as its factorization.

231976517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 79380, while the sum is 41.

The square root of 231976517 is about 15230.7753249794. The cubic root of 231976517 is about 614.4426324790.

The spelling of 231976517 in words is "two hundred thirty-one million, nine hundred seventy-six thousand, five hundred seventeen".