79689109 has 2 divisors, whose sum is σ = 79689110. Its totient is φ = 79689108.

The previous prime is 79689091. The next prime is 79689131. The reversal of 79689109 is 90198697.

Together with previous prime (79689091) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 79602084 + 87025 = 8922^2 + 295^2 .

It is an emirp because it is prime and its reverse (90198697) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 79689109 - 2⁷ = 79688981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79689139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39844554 + 39844555.

It is an arithmetic number, because the mean of its divisors is an integer number (39844555).

Almost surely, 2^79689109 is an apocalyptic number.

It is an amenable number.

79689109 is a deficient number, since it is larger than the sum of its proper divisors (1).

79689109 is an equidigital number, since it uses as much as digits as its factorization.

79689109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 244944, while the sum is 49.

The square root of 79689109 is about 8926.8756572499. The cubic root of 79689109 is about 430.3280514473.

The spelling of 79689109 in words is "seventy-nine million, six hundred eighty-nine thousand, one hundred nine".