390221 has 6 divisors (see below), whose sum is σ = 422730. Its totient is φ = 360048.

The previous prime is 390211. The next prime is 390223. The reversal of 390221 is 122093.

It can be written as a sum of positive squares in 3 ways, for example, as 13225 + 376996 = 115^2 + 614^2 .

It is not a de Polignac number, because 390221 - 2⁶ = 390157 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 390221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 986 + ... + 1323.

It is an arithmetic number, because the mean of its divisors is an integer number (70455).

2³⁹⁰²²¹ is an apocalyptic number.

It is an amenable number.

390221 is a deficient number, since it is larger than the sum of its proper divisors (32509).

390221 is a wasteful number, since it uses less digits than its factorization.

390221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2335 (or 2322 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 390221 is about 624.6767163902. The cubic root of 390221 is about 73.0752336281.

The spelling of 390221 in words is "three hundred ninety thousand, two hundred twenty-one".