399394 has 4 divisors (see below), whose sum is σ = 599094. Its totient is φ = 199696.

The previous prime is 399391. The next prime is 399401. The reversal of 399394 is 493993.

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., 354025 + 45369 = 595^2 + 213^2 .

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99847 + ... + 99850.

2³⁹⁹³⁹⁴ is an apocalyptic number.

399394 is a deficient number, since it is larger than the sum of its proper divisors (199700).

399394 is a wasteful number, since it uses less digits than its factorization.

399394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 199699.

The product of its digits is 26244, while the sum is 37.

The square root of 399394 is about 631.9762653771. The cubic root of 399394 is about 73.6434024484.

The spelling of 399394 in words is "three hundred ninety-nine thousand, three hundred ninety-four".