971257513 has 2 divisors, whose sum is σ = 971257514. Its totient is φ = 971257512.

The previous prime is 971257459. The next prime is 971257517. The reversal of 971257513 is 315752179.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 855738009 + 115519504 = 29253^2 + 10748^2 .

It is an emirp because it is prime and its reverse (315752179) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-971257513 is a prime.

It is not a weakly prime, because it can be changed into another prime (971257517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 485628756 + 485628757.

It is an arithmetic number, because the mean of its divisors is an integer number (485628757).

Almost surely, 2^971257513 is an apocalyptic number.

It is an amenable number.

971257513 is a deficient number, since it is larger than the sum of its proper divisors (1).

971257513 is an equidigital number, since it uses as much as digits as its factorization.

971257513 is an evil number, because the sum of its binary digits is even.

The product of its digits is 66150, while the sum is 40.

The square root of 971257513 is about 31165.0046205676. The cubic root of 971257513 is about 990.3258842804.

The spelling of 971257513 in words is "nine hundred seventy-one million, two hundred fifty-seven thousand, five hundred thirteen".