390643 has 8 divisors (see below), whose sum is σ = 451440. Its totient is φ = 334080.

The previous prime is 390581. The next prime is 390647. The reversal of 390643 is 346093.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-390643 is a prime.

390643 is a lucky number.

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

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 858 + ... + 1231.

It is an arithmetic number, because the mean of its divisors is an integer number (56430).

2³⁹⁰⁶⁴³ is an apocalyptic number.

390643 is a deficient number, since it is larger than the sum of its proper divisors (60797).

390643 is a wasteful number, since it uses less digits than its factorization.

390643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2117.

The product of its (nonzero) digits is 1944, while the sum is 25.

The square root of 390643 is about 625.0143998341. The cubic root of 390643 is about 73.1015662609.

The spelling of 390643 in words is "three hundred ninety thousand, six hundred forty-three".