664286220 has 144 divisors (see below), whose sum is σ = 2297786400. Its totient is φ = 153888768.

The previous prime is 664286219. The next prime is 664286261. The reversal of 664286220 is 22682466.

664286220 is a `hidden beast` number, since 6 + 6 + 4 + 28 + 622 + 0 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 31431 + ... + 48129.

It is an arithmetic number, because the mean of its divisors is an integer number (15956850).

Almost surely, 2^664286220 is an apocalyptic number.

664286220 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 664286220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1148893200).

664286220 is an abundant number, since it is smaller than the sum of its proper divisors (1633500180).

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

664286220 is a wasteful number, since it uses less digits than its factorization.

664286220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16744 (or 16739 counting only the distinct ones).

The product of its (nonzero) digits is 55296, while the sum is 36.

The square root of 664286220 is about 25773.7506001746. The cubic root of 664286220 is about 872.5394688812.

The spelling of 664286220 in words is "six hundred sixty-four million, two hundred eighty-six thousand, two hundred twenty".