726609 has 16 divisors (see below), whose sum is σ = 1078784. Its totient is φ = 432000.

The previous prime is 726601. The next prime is 726611. The reversal of 726609 is 906627.

It is not a de Polignac number, because 726609 - 2³ = 726601 is a prime.

It is a Duffinian number.

726609 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (726601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 909 + ... + 1509.

It is an arithmetic number, because the mean of its divisors is an integer number (67424).

2⁷²⁶⁶⁰⁹ is an apocalyptic number.

It is an amenable number.

726609 is a deficient number, since it is larger than the sum of its proper divisors (352175).

726609 is a wasteful number, since it uses less digits than its factorization.

726609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 648.

The product of its (nonzero) digits is 4536, while the sum is 30.

The square root of 726609 is about 852.4136319886. The cubic root of 726609 is about 89.9014971686.

The spelling of 726609 in words is "seven hundred twenty-six thousand, six hundred nine".