399415687 has 16 divisors (see below), whose sum is σ = 452818944. Its totient is φ = 349020000.

The previous prime is 399415673. The next prime is 399415741. The reversal of 399415687 is 786514993.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-399415687 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 (399415607) 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, 47613 + ... + 55369.

It is an arithmetic number, because the mean of its divisors is an integer number (28301184).

Almost surely, 2^399415687 is an apocalyptic number.

399415687 is a deficient number, since it is larger than the sum of its proper divisors (53403257).

399415687 is a wasteful number, since it uses less digits than its factorization.

399415687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7950.

The product of its digits is 1632960, while the sum is 52.

The square root of 399415687 is about 19985.3868363862. The cubic root of 399415687 is about 736.4473536411.

The spelling of 399415687 in words is "three hundred ninety-nine million, four hundred fifteen thousand, six hundred eighty-seven".