391317913 has 8 divisors (see below), whose sum is σ = 454800960. Its totient is φ = 329730000.

The previous prime is 391317853. The next prime is 391317919. The reversal of 391317913 is 319713193.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-391317913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (391317919) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 473338 + ... + 474163.

It is an arithmetic number, because the mean of its divisors is an integer number (56850120).

Almost surely, 2^391317913 is an apocalyptic number.

It is an amenable number.

391317913 is a deficient number, since it is larger than the sum of its proper divisors (63483047).

391317913 is an equidigital number, since it uses as much as digits as its factorization.

391317913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 947567.

The product of its digits is 15309, while the sum is 37.

The square root of 391317913 is about 19781.7570756493. The cubic root of 391317913 is about 731.4364117445.

The spelling of 391317913 in words is "three hundred ninety-one million, three hundred seventeen thousand, nine hundred thirteen".