3951891 has 12 divisors (see below), whose sum is σ = 5725720. Its totient is φ = 2626560.

The previous prime is 3951887. The next prime is 3951907. The reversal of 3951891 is 1981593.

It is a happy number.

3951891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 3951891 - 2² = 3951887 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3951811) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 4755 + ... + 5523.

Almost surely, 2^3951891 is an apocalyptic number.

3951891 is a deficient number, since it is larger than the sum of its proper divisors (1773829).

3951891 is a wasteful number, since it uses less digits than its factorization.

3951891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1346 (or 1343 counting only the distinct ones).

The product of its digits is 9720, while the sum is 36.

The square root of 3951891 is about 1987.9363671909. The cubic root of 3951891 is about 158.1011343110.

The spelling of 3951891 in words is "three million, nine hundred fifty-one thousand, eight hundred ninety-one".