399506 has 4 divisors (see below), whose sum is σ = 599262. Its totient is φ = 199752.

The previous prime is 399499. The next prime is 399523. The reversal of 399506 is 605993.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 312481 + 87025 = 559^2 + 295^2 .

It is an unprimeable number.

399506 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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, 99875 + ... + 99878.

2³⁹⁹⁵⁰⁶ is an apocalyptic number.

399506 is a deficient number, since it is larger than the sum of its proper divisors (199756).

399506 is a wasteful number, since it uses less digits than its factorization.

399506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199755.

The product of its (nonzero) digits is 7290, while the sum is 32.

The square root of 399506 is about 632.0648700885. The cubic root of 399506 is about 73.6502856183.

The spelling of 399506 in words is "three hundred ninety-nine thousand, five hundred six".