664722 has 12 divisors (see below), whose sum is σ = 1440270. Its totient is φ = 221568.

The previous prime is 664711. The next prime is 664739. The reversal of 664722 is 227466.

It can be written as a sum of positive squares in only one way, i.e., 505521 + 159201 = 711^2 + 399^2 .

It is an unprimeable number.

664722 is an untouchable number, because it is not equal to the sum of proper divisors of any 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 5 ways as a sum of consecutive naturals, for example, 18447 + ... + 18482.

2⁶⁶⁴⁷²² is an apocalyptic number.

664722 is an abundant number, since it is smaller than the sum of its proper divisors (775548).

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

664722 is a wasteful number, since it uses less digits than its factorization.

664722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36937 (or 36934 counting only the distinct ones).

The product of its digits is 4032, while the sum is 27.

The square root of 664722 is about 815.3048509607. The cubic root of 664722 is about 87.2730226079.

The spelling of 664722 in words is "six hundred sixty-four thousand, seven hundred twenty-two".