3991025 has 12 divisors (see below), whose sum is σ = 4975872. Its totient is φ = 3175440.

The previous prime is 3991021. The next prime is 3991037. The reversal of 3991025 is 5201993.

It is not a de Polignac number, because 3991025 - 2² = 3991021 is a prime.

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3991021) 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, 6272 + ... + 6878.

It is an arithmetic number, because the mean of its divisors is an integer number (414656).

Almost surely, 2^3991025 is an apocalyptic number.

It is an amenable number.

3991025 is a deficient number, since it is larger than the sum of its proper divisors (984847).

3991025 is a wasteful number, since it uses less digits than its factorization.

3991025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 880 (or 875 counting only the distinct ones).

The product of its (nonzero) digits is 2430, while the sum is 29.

The square root of 3991025 is about 1997.7549899825. The cubic root of 3991025 is about 158.6212919197.

The spelling of 3991025 in words is "three million, nine hundred ninety-one thousand, twenty-five".