79807018 has 4 divisors (see below), whose sum is σ = 119710530. Its totient is φ = 39903508.

The previous prime is 79807003. The next prime is 79807019. The reversal of 79807018 is 81070897.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 81070897 = 59 ⋅1374083.

It can be written as a sum of positive squares in only one way, i.e., 59799289 + 20007729 = 7733^2 + 4473^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (79807019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19951753 + ... + 19951756.

Almost surely, 2^79807018 is an apocalyptic number.

79807018 is a deficient number, since it is larger than the sum of its proper divisors (39903512).

79807018 is a wasteful number, since it uses less digits than its factorization.

79807018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39903511.

The product of its (nonzero) digits is 28224, while the sum is 40.

The square root of 79807018 is about 8933.4773744606. The cubic root of 79807018 is about 430.5401864406.

The spelling of 79807018 in words is "seventy-nine million, eight hundred seven thousand, eighteen".