3931688 has 8 divisors (see below), whose sum is σ = 7371930. Its totient is φ = 1965840.

The previous prime is 3931687. The next prime is 3931693. The reversal of 3931688 is 8861393.

It can be written as a sum of positive squares in only one way, i.e., 3928324 + 3364 = 1982^2 + 58^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (3931687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 245723 + ... + 245738.

Almost surely, 2^3931688 is an apocalyptic number.

It is an amenable number.

3931688 is a deficient number, since it is larger than the sum of its proper divisors (3440242).

3931688 is a wasteful number, since it uses less digits than its factorization.

3931688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 491467 (or 491463 counting only the distinct ones).

The product of its digits is 31104, while the sum is 38.

The square root of 3931688 is about 1982.8484561358. The cubic root of 3931688 is about 157.8312571176.

The spelling of 3931688 in words is "three million, nine hundred thirty-one thousand, six hundred eighty-eight".