3999779 has 4 divisors (see below), whose sum is σ = 4571184. Its totient is φ = 3428376.

The previous prime is 3999773. The next prime is 3999781. The reversal of 3999779 is 9779993.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 3999779 - 2⁴ = 3999763 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3999779.

It is not an unprimeable number, because it can be changed into a prime (3999773) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 285692 + ... + 285705.

It is an arithmetic number, because the mean of its divisors is an integer number (1142796).

Almost surely, 2^3999779 is an apocalyptic number.

3999779 is a deficient number, since it is larger than the sum of its proper divisors (571405).

3999779 is an equidigital number, since it uses as much as digits as its factorization.

3999779 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 571404.

The product of its digits is 964467, while the sum is 53.

The square root of 3999779 is about 1999.9447492368. The cubic root of 3999779 is about 158.7371816794.

It can be divided in two parts, 399 and 9779, that multiplied together give a triangular number (3901821 = T₂₇₉₃).

The spelling of 3999779 in words is "three million, nine hundred ninety-nine thousand, seven hundred seventy-nine".