3990661 has 16 divisors (see below), whose sum is σ = 4469760. Its totient is φ = 3548160.

The previous prime is 3990641. The next prime is 3990689. The reversal of 3990661 is 1660993.

3990661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3990661 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3990601) 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 15 ways as a sum of consecutive naturals, for example, 20581 + ... + 20773.

It is an arithmetic number, because the mean of its divisors is an integer number (279360).

Almost surely, 2^3990661 is an apocalyptic number.

3990661 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

3990661 is a deficient number, since it is larger than the sum of its proper divisors (479099).

3990661 is a wasteful number, since it uses less digits than its factorization.

3990661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276.

The product of its (nonzero) digits is 8748, while the sum is 34.

The square root of 3990661 is about 1997.6638856424. The cubic root of 3990661 is about 158.6164694404.

The spelling of 3990661 in words is "three million, nine hundred ninety thousand, six hundred sixty-one".