399903 has 16 divisors (see below), whose sum is σ = 618240. Its totient is φ = 225216.

The previous prime is 399899. The next prime is 399911. The reversal of 399903 is 309993.

It is not a de Polignac number, because 399903 - 2² = 399899 is a prime.

399903 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399913) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2808 + ... + 2946.

It is an arithmetic number, because the mean of its divisors is an integer number (38640).

2³⁹⁹⁹⁰³ is an apocalyptic number.

399903 is a deficient number, since it is larger than the sum of its proper divisors (218337).

399903 is a wasteful number, since it uses less digits than its factorization.

399903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286.

The product of its (nonzero) digits is 6561, while the sum is 33.

The square root of 399903 is about 632.3788421508. The cubic root of 399903 is about 73.6746736404.

It can be divided in two parts, 39990 and 3, that added together give a palindrome (39993).

The spelling of 399903 in words is "three hundred ninety-nine thousand, nine hundred three".