79505281 has 4 divisors (see below), whose sum is σ = 80292564. Its totient is φ = 78718000.

The previous prime is 79505233. The next prime is 79505381. The reversal of 79505281 is 18250597.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18250597 = 3803 ⋅4799.

It can be written as a sum of positive squares in 2 ways, for example, as 50183056 + 29322225 = 7084^2 + 5415^2 .

It is a cyclic number.

It is not a de Polignac number, because 79505281 - 2¹⁵ = 79472513 is a prime.

It is a super-2 number, since 2×79505281² = 12642179413777922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 79505281.

It is not an unprimeable number, because it can be changed into a prime (79505221) 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, 393490 + ... + 393691.

It is an arithmetic number, because the mean of its divisors is an integer number (20073141).

Almost surely, 2^79505281 is an apocalyptic number.

It is an amenable number.

79505281 is a deficient number, since it is larger than the sum of its proper divisors (787283).

79505281 is a wasteful number, since it uses less digits than its factorization.

79505281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 787282.

The product of its (nonzero) digits is 25200, while the sum is 37.

The square root of 79505281 is about 8916.5733889202. The cubic root of 79505281 is about 429.9969010052.

It can be divided in two parts, 7950 and 5281, that added together give a palindrome (13231).

The spelling of 79505281 in words is "seventy-nine million, five hundred five thousand, two hundred eighty-one".