664228 has 12 divisors (see below), whose sum is σ = 1169392. Its totient is φ = 330120.

The previous prime is 664211. The next prime is 664243. The reversal of 664228 is 822466.

664228 is nontrivially palindromic in base 7 and base 15.

664228 is an esthetic number in base 7, because in such base its adjacent digits differ by 1.

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 664196 and 664205.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 451 + ... + 1237.

2⁶⁶⁴²²⁸ is an apocalyptic number.

It is an amenable number.

664228 is a deficient number, since it is larger than the sum of its proper divisors (505164).

664228 is a wasteful number, since it uses less digits than its factorization.

664228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1002 (or 1000 counting only the distinct ones).

The product of its digits is 4608, while the sum is 28.

The square root of 664228 is about 815.0018404887. The cubic root of 664228 is about 87.2513977494.

It can be divided in two parts, 66422 and 8, that added together give a triangular number (66430 = T₃₆₄).

The spelling of 664228 in words is "six hundred sixty-four thousand, two hundred twenty-eight".