399937 has 2 divisors, whose sum is σ = 399938. Its totient is φ = 399936.

The previous prime is 399913. The next prime is 399941. The reversal of 399937 is 739993.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 323761 + 76176 = 569^2 + 276^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-399937 is a prime.

399937 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 399937.

It is not a weakly prime, because it can be changed into another prime (399137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199968 + 199969.

It is an arithmetic number, because the mean of its divisors is an integer number (199969).

2³⁹⁹⁹³⁷ is an apocalyptic number.

It is an amenable number.

399937 is a deficient number, since it is larger than the sum of its proper divisors (1).

399937 is an equidigital number, since it uses as much as digits as its factorization.

399937 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45927, while the sum is 40.

The square root of 399937 is about 632.4057241993. The cubic root of 399937 is about 73.6767615366.

It can be divided in two parts, 39993 and 7, that added together give a square (40000 = 200²).

The spelling of 399937 in words is "three hundred ninety-nine thousand, nine hundred thirty-seven".