971688257 has 4 divisors (see below), whose sum is σ = 978678960. Its totient is φ = 964697556.

The previous prime is 971688247. The next prime is 971688259. The reversal of 971688257 is 752886179.

971688257 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 971688257 - 2⁴ = 971688241 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 971688199 and 971688208.

It is not an unprimeable number, because it can be changed into a prime (971688259) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3495143 + ... + 3495420.

It is an arithmetic number, because the mean of its divisors is an integer number (244669740).

Almost surely, 2^971688257 is an apocalyptic number.

It is an amenable number.

971688257 is a deficient number, since it is larger than the sum of its proper divisors (6990703).

971688257 is a wasteful number, since it uses less digits than its factorization.

971688257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6990702.

The product of its digits is 1693440, while the sum is 53.

The square root of 971688257 is about 31171.9145546115. The cubic root of 971688257 is about 990.4722628606.

The spelling of 971688257 in words is "nine hundred seventy-one million, six hundred eighty-eight thousand, two hundred fifty-seven".