79865281 has 4 divisors (see below), whose sum is σ = 80598100. Its totient is φ = 79132464.

The previous prime is 79865263. The next prime is 79865311. The reversal of 79865281 is 18256897.

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 35509681 + 44355600 = 5959^2 + 6660^2 .

It is a cyclic number.

It is not a de Polignac number, because 79865281 - 2⁷ = 79865153 is a prime.

It is a super-2 number, since 2×79865281² = 12756926218417922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79865251) 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, 366246 + ... + 366463.

It is an arithmetic number, because the mean of its divisors is an integer number (20149525).

Almost surely, 2^79865281 is an apocalyptic number.

It is an amenable number.

79865281 is a deficient number, since it is larger than the sum of its proper divisors (732819).

79865281 is a wasteful number, since it uses less digits than its factorization.

79865281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 732818.

The product of its digits is 241920, while the sum is 46.

The square root of 79865281 is about 8936.7377157439. The cubic root of 79865281 is about 430.6449327050.

The spelling of 79865281 in words is "seventy-nine million, eight hundred sixty-five thousand, two hundred eighty-one".