3991859 has 8 divisors (see below), whose sum is σ = 4084800. Its totient is φ = 3900096.

The previous prime is 3991853. The next prime is 3991877. The reversal of 3991859 is 9581993.

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 3991859 - 2¹⁶ = 3926323 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3991853) by changing a digit.

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 in 7 ways as a sum of consecutive naturals, for example, 10694 + ... + 11060.

It is an arithmetic number, because the mean of its divisors is an integer number (510600).

Almost surely, 2^3991859 is an apocalyptic number.

3991859 is a deficient number, since it is larger than the sum of its proper divisors (92941).

3991859 is a wasteful number, since it uses less digits than its factorization.

3991859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 589.

The product of its digits is 87480, while the sum is 44.

The square root of 3991859 is about 1997.9637133842. The cubic root of 3991859 is about 158.6323401211.

The spelling of 3991859 in words is "three million, nine hundred ninety-one thousand, eight hundred fifty-nine".