351317991 has 16 divisors (see below), whose sum is σ = 472693760. Its totient is φ = 232087680.

The previous prime is 351317969. The next prime is 351318007. The reversal of 351317991 is 199713153.

It is not a de Polignac number, because 351317991 - 2⁶ = 351317927 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (351317191) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 160140 + ... + 162318.

It is an arithmetic number, because the mean of its divisors is an integer number (29543360).

Almost surely, 2^351317991 is an apocalyptic number.

351317991 is a deficient number, since it is larger than the sum of its proper divisors (121375769).

351317991 is a wasteful number, since it uses less digits than its factorization.

351317991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2646.

The product of its digits is 25515, while the sum is 39.

The square root of 351317991 is about 18743.4786259115. The cubic root of 351317991 is about 705.6133628936.

The spelling of 351317991 in words is "three hundred fifty-one million, three hundred seventeen thousand, nine hundred ninety-one".