391459971 has 24 divisors (see below), whose sum is σ = 626755584. Its totient is φ = 216473040.

The previous prime is 391459967. The next prime is 391459987. The reversal of 391459971 is 179954193.

It is not a de Polignac number, because 391459971 - 2² = 391459967 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 391459971.

It is not an unprimeable number, because it can be changed into a prime (391459921) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38395 + ... + 47508.

It is an arithmetic number, because the mean of its divisors is an integer number (26114816).

Almost surely, 2^391459971 is an apocalyptic number.

391459971 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

391459971 is a deficient number, since it is larger than the sum of its proper divisors (235295613).

391459971 is a wasteful number, since it uses less digits than its factorization.

391459971 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85951 (or 85944 counting only the distinct ones).

The product of its digits is 306180, while the sum is 48.

The square root of 391459971 is about 19785.3473813325. The cubic root of 391459971 is about 731.5249108219.

The spelling of 391459971 in words is "three hundred ninety-one million, four hundred fifty-nine thousand, nine hundred seventy-one".