722644 has 18 divisors (see below), whose sum is σ = 1370670. Its totient is φ = 333216.

The previous prime is 722639. The next prime is 722663. The reversal of 722644 is 446227.

722644 = T₆₂ + T₆₃ + ... + T₁₆₅.

It can be written as a sum of positive squares in 3 ways, for example, as 144 + 722500 = 12^2 + 850^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 142 + ... + 1210.

2⁷²²⁶⁴⁴ is an apocalyptic number.

It is an amenable number.

722644 is a deficient number, since it is larger than the sum of its proper divisors (648026).

722644 is a wasteful number, since it uses less digits than its factorization.

722644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1099 (or 1084 counting only the distinct ones).

The product of its digits is 2688, while the sum is 25.

The square root of 722644 is about 850.0847016621. The cubic root of 722644 is about 89.7376723369.

The spelling of 722644 in words is "seven hundred twenty-two thousand, six hundred forty-four".