399604787 has 4 divisors (see below), whose sum is σ = 412495296. Its totient is φ = 386714280.

The previous prime is 399604753. The next prime is 399604837. The reversal of 399604787 is 787406993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 787406993 = 21401 ⋅36793.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-399604787 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399604747) 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 3 ways as a sum of consecutive naturals, for example, 6445208 + ... + 6445269.

It is an arithmetic number, because the mean of its divisors is an integer number (103123824).

Almost surely, 2^399604787 is an apocalyptic number.

399604787 is a deficient number, since it is larger than the sum of its proper divisors (12890509).

399604787 is a wasteful number, since it uses less digits than its factorization.

399604787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12890508.

The product of its (nonzero) digits is 2286144, while the sum is 53.

The square root of 399604787 is about 19990.1172332730. The cubic root of 399604787 is about 736.5635569078.

The spelling of 399604787 in words is "three hundred ninety-nine million, six hundred four thousand, seven hundred eighty-seven".