3991256 has 8 divisors (see below), whose sum is σ = 7483620. Its totient is φ = 1995624.

The previous prime is 3991237. The next prime is 3991261. The reversal of 3991256 is 6521993.

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

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 249446 + ... + 249461.

Almost surely, 2^3991256 is an apocalyptic number.

It is an amenable number.

3991256 is a deficient number, since it is larger than the sum of its proper divisors (3492364).

3991256 is a wasteful number, since it uses less digits than its factorization.

3991256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498913 (or 498909 counting only the distinct ones).

The product of its digits is 14580, while the sum is 35.

The square root of 3991256 is about 1997.8128040435. The cubic root of 3991256 is about 158.6243521871.

The spelling of 3991256 in words is "three million, nine hundred ninety-one thousand, two hundred fifty-six".