331391390 has 16 divisors (see below), whose sum is σ = 650732400. Its totient is φ = 120505920.

The previous prime is 331391363. The next prime is 331391393. The reversal of 331391390 is 93193133.

It is a super-2 number, since 2×331391390² = 219640506732264200, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (331391393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1506215 + ... + 1506434.

It is an arithmetic number, because the mean of its divisors is an integer number (40670775).

Almost surely, 2^331391390 is an apocalyptic number.

331391390 is a deficient number, since it is larger than the sum of its proper divisors (319341010).

331391390 is a wasteful number, since it uses less digits than its factorization.

331391390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3012667.

The product of its (nonzero) digits is 6561, while the sum is 32.

The square root of 331391390 is about 18204.1585908275. The cubic root of 331391390 is about 692.0121827853.

The spelling of 331391390 in words is "three hundred thirty-one million, three hundred ninety-one thousand, three hundred ninety".