399955 has 8 divisors (see below), whose sum is σ = 491904. Its totient is φ = 312000.

The previous prime is 399953. The next prime is 399979. The reversal of 399955 is 559993.

It is a happy number.

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

It is not a de Polignac number, because 399955 - 2¹ = 399953 is a prime.

It is a Duffinian 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, 771 + ... + 1180.

It is an arithmetic number, because the mean of its divisors is an integer number (61488).

2³⁹⁹⁹⁵⁵ is an apocalyptic number.

399955 is a deficient number, since it is larger than the sum of its proper divisors (91949).

399955 is a wasteful number, since it uses less digits than its factorization.

399955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1997.

The product of its digits is 54675, while the sum is 40.

The square root of 399955 is about 632.4199554094. The cubic root of 399955 is about 73.6778668456.

It can be divided in two parts, 39995 and 5, that added together give a square (40000 = 200²).

The spelling of 399955 in words is "three hundred ninety-nine thousand, nine hundred fifty-five".