3999165 has 16 divisors (see below), whose sum is σ = 6775488. Its totient is φ = 2007296.

The previous prime is 3999161. The next prime is 3999209. The reversal of 3999165 is 5619993.

It is a cyclic number.

It is not a de Polignac number, because 3999165 - 2² = 3999161 is a prime.

It is an Ulam number.

3999165 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3999161) 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 15 ways as a sum of consecutive naturals, for example, 7587 + ... + 8096.

It is an arithmetic number, because the mean of its divisors is an integer number (423468).

Almost surely, 2^3999165 is an apocalyptic number.

It is an amenable number.

3999165 is a deficient number, since it is larger than the sum of its proper divisors (2776323).

3999165 is a wasteful number, since it uses less digits than its factorization.

3999165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15708.

The product of its digits is 65610, while the sum is 42.

The square root of 3999165 is about 1999.7912391047. The cubic root of 3999165 is about 158.7290587625.

The spelling of 3999165 in words is "three million, nine hundred ninety-nine thousand, one hundred sixty-five".