3999807 has 16 divisors (see below), whose sum is σ = 6772480. Its totient is φ = 2285496.

The previous prime is 3999803. The next prime is 3999851. The reversal of 3999807 is 7089993.

It is a happy number.

It is not a de Polignac number, because 3999807 - 2² = 3999803 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 (3999803) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10393 + ... + 10770.

It is an arithmetic number, because the mean of its divisors is an integer number (423280).

Almost surely, 2^3999807 is an apocalyptic number.

3999807 is a deficient number, since it is larger than the sum of its proper divisors (2772673).

3999807 is a wasteful number, since it uses less digits than its factorization.

3999807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21179 (or 21173 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The square root of 3999807 is about 1999.9517494180. The cubic root of 3999807 is about 158.7375520857.

The spelling of 3999807 in words is "three million, nine hundred ninety-nine thousand, eight hundred seven".