399843 has 16 divisors (see below), whose sum is σ = 604800. Its totient is φ = 261000.

The previous prime is 399793. The next prime is 399851. The reversal of 399843 is 348993.

It is not a de Polignac number, because 399843 - 2⁸ = 399587 is a prime.

399843 is a lucky number.

It is a zygodrome in base 2.

It is a junction number, because it is equal to n+sod(n) for n = 399798 and 399807.

It is not an unprimeable number, because it can be changed into a prime (399853) 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, 1468 + ... + 1718.

It is an arithmetic number, because the mean of its divisors is an integer number (37800).

2³⁹⁹⁸⁴³ is an apocalyptic number.

399843 is a deficient number, since it is larger than the sum of its proper divisors (204957).

399843 is a wasteful number, since it uses less digits than its factorization.

399843 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319 (or 313 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 399843 is about 632.3314004539. The cubic root of 399843 is about 73.6709888289.

The spelling of 399843 in words is "three hundred ninety-nine thousand, eight hundred forty-three".