7991317 has 4 divisors (see below), whose sum is σ = 8045100. Its totient is φ = 7937536.

The previous prime is 7991311. The next prime is 7991329. The reversal of 7991317 is 7131997.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7131997 = 269 ⋅26513.

It can be written as a sum of positive squares in 2 ways, for example, as 1069156 + 6922161 = 1034^2 + 2631^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7991317 is a prime.

It is a super-2 number, since 2×7991317² = 127722294788978, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7991311) 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, 26668 + ... + 26965.

It is an arithmetic number, because the mean of its divisors is an integer number (2011275).

Almost surely, 2^7991317 is an apocalyptic number.

It is an amenable number.

7991317 is a deficient number, since it is larger than the sum of its proper divisors (53783).

7991317 is a wasteful number, since it uses less digits than its factorization.

7991317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53782.

The product of its digits is 11907, while the sum is 37.

The square root of 7991317 is about 2826.8917559751. The cubic root of 7991317 is about 199.9276154722.

It can be divided in two parts, 799 and 1317, that added together give a square (2116 = 46²).

The spelling of 7991317 in words is "seven million, nine hundred ninety-one thousand, three hundred seventeen".