79118622721 has 4 divisors (see below), whose sum is σ = 80007596100. Its totient is φ = 78229649344.

The previous prime is 79118622719. The next prime is 79118622731. The reversal of 79118622721 is 12722681197.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12722681197 = 317 ⋅40134641.

It can be written as a sum of positive squares in 2 ways, for example, as 25062372721 + 54056250000 = 158311^2 + 232500^2 .

It is a cyclic number.

It is not a de Polignac number, because 79118622721 - 2¹ = 79118622719 is a prime.

It is a super-2 number, since 2×79118622721² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (79118622731) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 444486556 + ... + 444486733.

It is an arithmetic number, because the mean of its divisors is an integer number (20001899025).

Almost surely, 2^79118622721 is an apocalyptic number.

It is an amenable number.

79118622721 is a deficient number, since it is larger than the sum of its proper divisors (888973379).

79118622721 is an equidigital number, since it uses as much as digits as its factorization.

79118622721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 888973378.

The product of its digits is 169344, while the sum is 46.

The spelling of 79118622721 in words is "seventy-nine billion, one hundred eighteen million, six hundred twenty-two thousand, seven hundred twenty-one".