391887164 has 12 divisors (see below), whose sum is σ = 691872384. Its totient is φ = 194209344.

The previous prime is 391887157. The next prime is 391887173. The reversal of 391887164 is 461788193.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 433052 + ... + 433955.

It is an arithmetic number, because the mean of its divisors is an integer number (57656032).

Almost surely, 2^391887164 is an apocalyptic number.

It is an amenable number.

391887164 is a deficient number, since it is larger than the sum of its proper divisors (299985220).

391887164 is a wasteful number, since it uses less digits than its factorization.

391887164 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 867124 (or 867122 counting only the distinct ones).

The product of its digits is 290304, while the sum is 47.

The square root of 391887164 is about 19796.1401288231. The cubic root of 391887164 is about 731.7909139361.

The spelling of 391887164 in words is "three hundred ninety-one million, eight hundred eighty-seven thousand, one hundred sixty-four".