390221568 has 216 divisors, whose sum is σ = 1248352560. Its totient is φ = 116244480.

The previous prime is 390221567. The next prime is 390221569. The reversal of 390221568 is 865122093.

390221568 is a `hidden beast` number, since 3 + 90 + 2 + 2 + 1 + 568 = 666.

It is an interprime number because it is at equal distance from previous prime (390221567) and next prime (390221569).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390221567) 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 23 ways as a sum of consecutive naturals, for example, 2255530 + ... + 2255702.

It is an arithmetic number, because the mean of its divisors is an integer number (5779410).

Almost surely, 2^390221568 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 390221568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (624176280).

390221568 is an abundant number, since it is smaller than the sum of its proper divisors (858130992).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

390221568 is a wasteful number, since it uses less digits than its factorization.

390221568 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295 (or 278 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 390221568 is about 19754.0266275005. The cubic root of 390221568 is about 730.7526908384.

The spelling of 390221568 in words is "three hundred ninety million, two hundred twenty-one thousand, five hundred sixty-eight".