331688987 has 12 divisors (see below), whose sum is σ = 388795176. Its totient is φ = 282129120.

The previous prime is 331688977. The next prime is 331689031. The reversal of 331688987 is 789886133.

It is not a de Polignac number, because 331688987 - 2⁶ = 331688923 is a prime.

It is a super-2 number, since 2×331688987² = 220035168194172338, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (331688977) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 19418 + ... + 32255.

It is an arithmetic number, because the mean of its divisors is an integer number (32399598).

Almost surely, 2^331688987 is an apocalyptic number.

331688987 is a deficient number, since it is larger than the sum of its proper divisors (57106189).

331688987 is a wasteful number, since it uses less digits than its factorization.

331688987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51818 (or 51811 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 53.

The square root of 331688987 is about 18212.3306306469. The cubic root of 331688987 is about 692.2192683645.

The spelling of 331688987 in words is "three hundred thirty-one million, six hundred eighty-eight thousand, nine hundred eighty-seven".