399768609 has 16 divisors (see below), whose sum is σ = 549106688. Its totient is φ = 258515712.

The previous prime is 399768599. The next prime is 399768613. The reversal of 399768609 is 906867993.

It is not a de Polignac number, because 399768609 - 2⁹ = 399768097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399768619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32064 + ... + 42750.

It is an arithmetic number, because the mean of its divisors is an integer number (34319168).

Almost surely, 2^399768609 is an apocalyptic number.

It is an amenable number.

399768609 is a deficient number, since it is larger than the sum of its proper divisors (149338079).

399768609 is a wasteful number, since it uses less digits than its factorization.

399768609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11064.

The product of its (nonzero) digits is 4408992, while the sum is 57.

The square root of 399768609 is about 19994.2143881674. The cubic root of 399768609 is about 736.6641970347.

The spelling of 399768609 in words is "three hundred ninety-nine million, seven hundred sixty-eight thousand, six hundred nine".