3899991 has 8 divisors (see below), whose sum is σ = 5209344. Its totient is φ = 2595320.

The previous prime is 3899989. The next prime is 3900067. The reversal of 3899991 is 1999983.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 3899991 - 2¹ = 3899989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 3899991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3899941) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2020 + ... + 3446.

It is an arithmetic number, because the mean of its divisors is an integer number (651168).

Almost surely, 2^3899991 is an apocalyptic number.

3899991 is a deficient number, since it is larger than the sum of its proper divisors (1309353).

3899991 is a wasteful number, since it uses less digits than its factorization.

3899991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2341.

The product of its digits is 157464, while the sum is 48.

The square root of 3899991 is about 1974.8394871483. The cubic root of 3899991 is about 157.4059705814.

The spelling of 3899991 in words is "three million, eight hundred ninety-nine thousand, nine hundred ninety-one".