399959 has 8 divisors (see below), whose sum is σ = 484128. Its totient is φ = 322560.

The previous prime is 399953. The next prime is 399979. The reversal of 399959 is 959993.

399959 = T₂₃₂ + T₂₃₃ + ... + T₂₄₅.

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

It is not a de Polignac number, because 399959 - 2¹⁶ = 334423 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399953) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1562 + ... + 1799.

It is an arithmetic number, because the mean of its divisors is an integer number (60516).

2³⁹⁹⁹⁵⁹ is an apocalyptic number.

399959 is a deficient number, since it is larger than the sum of its proper divisors (84169).

399959 is a wasteful number, since it uses less digits than its factorization.

399959 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3385.

The product of its digits is 98415, while the sum is 44.

The square root of 399959 is about 632.4231178570. The cubic root of 399959 is about 73.6781124653.

It can be divided in two parts, 39995 and 9, that added together give a palindrome (40004).

The spelling of 399959 in words is "three hundred ninety-nine thousand, nine hundred fifty-nine".