399865285 has 8 divisors (see below), whose sum is σ = 480082680. Its totient is φ = 319729344.

The previous prime is 399865273. The next prime is 399865307. The reversal of 399865285 is 582568993.

It can be written as a sum of positive squares in 4 ways, for example, as 5008644 + 394856641 = 2238^2 + 19871^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 399865285 - 2¹⁷ = 399734213 is a prime.

It is a super-2 number, since 2×399865285² = 319784492296262450, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8982 + ... + 29671.

It is an arithmetic number, because the mean of its divisors is an integer number (60010335).

Almost surely, 2^399865285 is an apocalyptic number.

It is an amenable number.

399865285 is a deficient number, since it is larger than the sum of its proper divisors (80217395).

399865285 is a wasteful number, since it uses less digits than its factorization.

399865285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40727.

The product of its digits is 4665600, while the sum is 55.

The square root of 399865285 is about 19996.6318413877. The cubic root of 399865285 is about 736.7235747232.

The spelling of 399865285 in words is "three hundred ninety-nine million, eight hundred sixty-five thousand, two hundred eighty-five".