79819669 has 2 divisors, whose sum is σ = 79819670. Its totient is φ = 79819668.

The previous prime is 79819667. The next prime is 79819679. The reversal of 79819669 is 96691897.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43362225 + 36457444 = 6585^2 + 6038^2 .

It is a cyclic number.

It is not a de Polignac number, because 79819669 - 2¹ = 79819667 is a prime.

It is a super-2 number, since 2×79819669² = 12742359118539122, which contains 22 as substring.

Together with 79819667, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79819667) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39909834 + 39909835.

It is an arithmetic number, because the mean of its divisors is an integer number (39909835).

Almost surely, 2^79819669 is an apocalyptic number.

It is an amenable number.

79819669 is a deficient number, since it is larger than the sum of its proper divisors (1).

79819669 is an equidigital number, since it uses as much as digits as its factorization.

79819669 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1469664, while the sum is 55.

The square root of 79819669 is about 8934.1854133435. The cubic root of 79819669 is about 430.5629349668.

The spelling of 79819669 in words is "seventy-nine million, eight hundred nineteen thousand, six hundred sixty-nine".