399764 has 12 divisors (see below), whose sum is σ = 705600. Its totient is φ = 198168.

The previous prime is 399761. The next prime is 399769. The reversal of 399764 is 467993.

It is a super-2 number, since 2×399764² = 319622511392, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399761) 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, 197 + ... + 915.

It is an arithmetic number, because the mean of its divisors is an integer number (58800).

2³⁹⁹⁷⁶⁴ is an apocalyptic number.

It is an amenable number.

399764 is a deficient number, since it is larger than the sum of its proper divisors (305836).

399764 is a wasteful number, since it uses less digits than its factorization.

399764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 862 (or 860 counting only the distinct ones).

The product of its digits is 40824, while the sum is 38.

The square root of 399764 is about 632.2689301239. The cubic root of 399764 is about 73.6661365982. Note that the first 3 decimals are identical.

The spelling of 399764 in words is "three hundred ninety-nine thousand, seven hundred sixty-four".