391976 has 16 divisors (see below), whose sum is σ = 791700. Its totient is φ = 180864.

The previous prime is 391967. The next prime is 391987. The reversal of 391976 is 679193.

It can be written as a sum of positive squares in 2 ways, for example, as 391876 + 100 = 626^2 + 10^2 .

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1781 + ... + 1988.

2³⁹¹⁹⁷⁶ is an apocalyptic number.

It is an amenable number.

391976 is an abundant number, since it is smaller than the sum of its proper divisors (399724).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

391976 is a wasteful number, since it uses less digits than its factorization.

391976 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3788 (or 3784 counting only the distinct ones).

The product of its digits is 10206, while the sum is 35.

The square root of 391976 is about 626.0798671096. The cubic root of 391976 is about 73.1846205758.

The spelling of 391976 in words is "three hundred ninety-one thousand, nine hundred seventy-six".