79829809 has 4 divisors (see below), whose sum is σ = 79948404. Its totient is φ = 79711216.

The previous prime is 79829791. The next prime is 79829821. The reversal of 79829809 is 90892897.

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 64400625 + 15429184 = 8025^2 + 3928^2 .

It is a cyclic number.

It is not a de Polignac number, because 79829809 - 2⁵ = 79829777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79829209) 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, 58282 + ... + 59635.

It is an arithmetic number, because the mean of its divisors is an integer number (19987101).

Almost surely, 2^79829809 is an apocalyptic number.

It is an amenable number.

79829809 is a deficient number, since it is larger than the sum of its proper divisors (118595).

79829809 is a wasteful number, since it uses less digits than its factorization.

79829809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 118594.

The product of its (nonzero) digits is 653184, while the sum is 52.

The square root of 79829809 is about 8934.7528785076. The cubic root of 79829809 is about 430.5811665770.

The spelling of 79829809 in words is "seventy-nine million, eight hundred twenty-nine thousand, eight hundred nine".