399849 has 4 divisors (see below), whose sum is σ = 533136. Its totient is φ = 266564.

The previous prime is 399793. The next prime is 399851. The reversal of 399849 is 948993.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 399849 - 2¹⁷ = 268777 is a prime.

It is an Ulam number.

It is a D-number.

It is a self number, because there is not a number n which added to its sum of digits gives 399849.

It is not an unprimeable number, because it can be changed into a prime (399899) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 66639 + ... + 66644.

It is an arithmetic number, because the mean of its divisors is an integer number (133284).

2³⁹⁹⁸⁴⁹ is an apocalyptic number.

It is an amenable number.

399849 is a deficient number, since it is larger than the sum of its proper divisors (133287).

399849 is a wasteful number, since it uses less digits than its factorization.

399849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133286.

The product of its digits is 69984, while the sum is 42.

The square root of 399849 is about 632.3361447838. The cubic root of 399849 is about 73.6713573266.

It can be divided in two parts, 39984 and 9, that added together give a palindrome (39993).

The spelling of 399849 in words is "three hundred ninety-nine thousand, eight hundred forty-nine".