391849317 has 12 divisors (see below), whose sum is σ = 566573280. Its totient is φ = 260970408.

The previous prime is 391849313. The next prime is 391849349. The reversal of 391849317 is 713948193.

It is not a de Polignac number, because 391849317 - 2² = 391849313 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (391849313) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12193 + ... + 30534.

It is an arithmetic number, because the mean of its divisors is an integer number (47214440).

Almost surely, 2^391849317 is an apocalyptic number.

It is an amenable number.

391849317 is a deficient number, since it is larger than the sum of its proper divisors (174723963).

391849317 is a wasteful number, since it uses less digits than its factorization.

391849317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43752 (or 43749 counting only the distinct ones).

The product of its digits is 163296, while the sum is 45.

The square root of 391849317 is about 19795.1841870693. The cubic root of 391849317 is about 731.7673552990.

It can be divided in two parts, 3918 and 49317, that added together give a palindrome (53235).

The spelling of 391849317 in words is "three hundred ninety-one million, eight hundred forty-nine thousand, three hundred seventeen".