623709 has 12 divisors (see below), whose sum is σ = 925756. Its totient is φ = 404352.

The previous prime is 623699. The next prime is 623717. The reversal of 623709 is 907326.

It can be written as a sum of positive squares in 2 ways, for example, as 260100 + 363609 = 510^2 + 603^2 .

It is not a de Polignac number, because 623709 - 2⁵ = 623677 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (623719) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 604 + ... + 1269.

2⁶²³⁷⁰⁹ is an apocalyptic number.

It is an amenable number.

623709 is a deficient number, since it is larger than the sum of its proper divisors (302047).

623709 is a wasteful number, since it uses less digits than its factorization.

623709 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1916 (or 1913 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 27.

The square root of 623709 is about 789.7524928736. The cubic root of 623709 is about 85.4398879822.

The spelling of 623709 in words is "six hundred twenty-three thousand, seven hundred nine".