399687287 has 6 divisors (see below), whose sum is σ = 421831008. Its totient is φ = 378650772.

The previous prime is 399687241. The next prime is 399687313. The reversal of 399687287 is 782786993.

It is not a de Polignac number, because 399687287 - 2²⁰ = 398638711 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399681287) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 553223 + ... + 553944.

It is an arithmetic number, because the mean of its divisors is an integer number (70305168).

Almost surely, 2^399687287 is an apocalyptic number.

399687287 is a deficient number, since it is larger than the sum of its proper divisors (22143721).

399687287 is a wasteful number, since it uses less digits than its factorization.

399687287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1107205 (or 1107186 counting only the distinct ones).

The product of its digits is 9144576, while the sum is 59.

The square root of 399687287 is about 19992.1806464427. The cubic root of 399687287 is about 736.6142422466.

The spelling of 399687287 in words is "three hundred ninety-nine million, six hundred eighty-seven thousand, two hundred eighty-seven".