723280 has 20 divisors (see below), whose sum is σ = 1681812. Its totient is φ = 289280.

The previous prime is 723271. The next prime is 723287. The reversal of 723280 is 82327.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 553536 + 169744 = 744^2 + 412^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (723287) by changing a digit.

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, 4441 + ... + 4600.

2⁷²³²⁸⁰ is an apocalyptic number.

It is an amenable number.

723280 is an abundant number, since it is smaller than the sum of its proper divisors (958532).

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

723280 is a wasteful number, since it uses less digits than its factorization.

723280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9054 (or 9048 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 22.

The square root of 723280 is about 850.4586997615. The cubic root of 723280 is about 89.7639907013.

The spelling of 723280 in words is "seven hundred twenty-three thousand, two hundred eighty".