399297705987 has 4 divisors (see below), whose sum is σ = 532396941320. Its totient is φ = 266198470656.

The previous prime is 399297705979. The next prime is 399297706033. The reversal of 399297705987 is 789507792993.

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

It is not a de Polignac number, because 399297705987 - 2³ = 399297705979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (399297715987) 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, 66549617662 + ... + 66549617667.

It is an arithmetic number, because the mean of its divisors is an integer number (133099235330).

Almost surely, 2^399297705987 is an apocalyptic number.

399297705987 is a deficient number, since it is larger than the sum of its proper divisors (133099235333).

399297705987 is a wasteful number, since it uses less digits than its factorization.

399297705987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133099235332.

The product of its (nonzero) digits is 540101520, while the sum is 75.

The spelling of 399297705987 in words is "three hundred ninety-nine billion, two hundred ninety-seven million, seven hundred five thousand, nine hundred eighty-seven".