813709 has 8 divisors (see below), whose sum is σ = 893592. Its totient is φ = 736320.

The previous prime is 813707. The next prime is 813721. The reversal of 813709 is 907318.

813709 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 228484 + 585225 = 478^2 + 765^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 813709 - 2¹ = 813707 is a prime.

It is a Duffinian number.

813709 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (813707) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 99 + ... + 1279.

It is an arithmetic number, because the mean of its divisors is an integer number (111699).

2⁸¹³⁷⁰⁹ is an apocalyptic number.

It is an amenable number.

813709 is a deficient number, since it is larger than the sum of its proper divisors (79883).

813709 is a wasteful number, since it uses less digits than its factorization.

813709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1247.

The product of its (nonzero) digits is 1512, while the sum is 28.

The square root of 813709 is about 902.0582021134. The cubic root of 813709 is about 93.3590391213.

The spelling of 813709 in words is "eight hundred thirteen thousand, seven hundred nine".