331891 has 8 divisors (see below), whose sum is σ = 401760. Its totient is φ = 267648.

The previous prime is 331889. The next prime is 331897. The reversal of 331891 is 198133.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 331891 - 2¹ = 331889 is a prime.

It is a super-2 number, since 2×331891² = 220303271762, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (331897) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1276 + ... + 1513.

It is an arithmetic number, because the mean of its divisors is an integer number (50220).

2³³¹⁸⁹¹ is an apocalyptic number.

331891 is a deficient number, since it is larger than the sum of its proper divisors (69869).

331891 is a wasteful number, since it uses less digits than its factorization.

331891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2813.

The product of its digits is 648, while the sum is 25.

The square root of 331891 is about 576.0998177399. The cubic root of 331891 is about 69.2359770378.

The spelling of 331891 in words is "three hundred thirty-one thousand, eight hundred ninety-one".