679813 has 4 divisors (see below), whose sum is σ = 719820. Its totient is φ = 639808.

The previous prime is 679807. The next prime is 679823. The reversal of 679813 is 318976.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 311364 + 368449 = 558^2 + 607^2 .

It is a cyclic number.

It is not a de Polignac number, because 679813 - 2⁵ = 679781 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (679823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19978 + ... + 20011.

It is an arithmetic number, because the mean of its divisors is an integer number (179955).

2⁶⁷⁹⁸¹³ is an apocalyptic number.

It is an amenable number.

679813 is a deficient number, since it is larger than the sum of its proper divisors (40007).

679813 is a wasteful number, since it uses less digits than its factorization.

679813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40006.

The product of its digits is 9072, while the sum is 34.

The square root of 679813 is about 824.5077319225. The cubic root of 679813 is about 87.9285318497.

The spelling of 679813 in words is "six hundred seventy-nine thousand, eight hundred thirteen".