399653 has 4 divisors (see below), whose sum is σ = 423180. Its totient is φ = 376128.

The previous prime is 399647. The next prime is 399667. The reversal of 399653 is 356993.

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

It can be written as a sum of positive squares in 2 ways, for example, as 362404 + 37249 = 602^2 + 193^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-399653 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399613) 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, 11738 + ... + 11771.

It is an arithmetic number, because the mean of its divisors is an integer number (105795).

2³⁹⁹⁶⁵³ is an apocalyptic number.

It is an amenable number.

399653 is a deficient number, since it is larger than the sum of its proper divisors (23527).

399653 is a wasteful number, since it uses less digits than its factorization.

399653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23526.

The product of its digits is 21870, while the sum is 35.

The square root of 399653 is about 632.1811449260. The cubic root of 399653 is about 73.6593178267.

The spelling of 399653 in words is "three hundred ninety-nine thousand, six hundred fifty-three".