79805617 has 4 divisors (see below), whose sum is σ = 79824420. Its totient is φ = 79786816.

The previous prime is 79805603. The next prime is 79805647. The reversal of 79805617 is 71650897.

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 4532641 + 75272976 = 2129^2 + 8676^2 .

It is a cyclic number.

It is not a de Polignac number, because 79805617 - 2²³ = 71417009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79805647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 309 + ... + 12637.

It is an arithmetic number, because the mean of its divisors is an integer number (19956105).

Almost surely, 2^79805617 is an apocalyptic number.

It is an amenable number.

79805617 is a deficient number, since it is larger than the sum of its proper divisors (18803).

79805617 is a wasteful number, since it uses less digits than its factorization.

79805617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18802.

The product of its (nonzero) digits is 105840, while the sum is 43.

The square root of 79805617 is about 8933.3989612017. The cubic root of 79805617 is about 430.5376670701.

The spelling of 79805617 in words is "seventy-nine million, eight hundred five thousand, six hundred seventeen".