390644 has 12 divisors (see below), whose sum is σ = 695268. Its totient is φ = 192000.

The previous prime is 390581. The next prime is 390647. The reversal of 390644 is 446093.

It can be written as a sum of positive squares in 2 ways, for example, as 220900 + 169744 = 470^2 + 412^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 557 + ... + 1044.

It is an arithmetic number, because the mean of its divisors is an integer number (57939).

2³⁹⁰⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

390644 is a deficient number, since it is larger than the sum of its proper divisors (304624).

390644 is a wasteful number, since it uses less digits than its factorization.

390644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1666 (or 1664 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 390644 is about 625.0151998152. The cubic root of 390644 is about 73.1016286380.

The spelling of 390644 in words is "three hundred ninety thousand, six hundred forty-four".