79668 has 18 divisors (see below), whose sum is σ = 201474. Its totient is φ = 26544.

The previous prime is 79657. The next prime is 79669. The reversal of 79668 is 86697.

It can be written as a sum of positive squares in only one way, i.e., 79524 + 144 = 282^2 + 12^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 2213 = 79668 / (7 + 9 + 6 + 6 + 8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79669) by changing a digit.

79668 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1071 + ... + 1142.

It is an arithmetic number, because the mean of its divisors is an integer number (11193).

2⁷⁹⁶⁶⁸ is an apocalyptic number.

It is an amenable number.

79668 is an abundant number, since it is smaller than the sum of its proper divisors (121806).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

79668 is a wasteful number, since it uses less digits than its factorization.

79668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2223 (or 2218 counting only the distinct ones).

The product of its digits is 18144, while the sum is 36.

The square root of 79668 is about 282.2552036721. The cubic root of 79668 is about 43.0290051286.

It can be divided in two parts, 79 and 668, that added together give a palindrome (747).

The spelling of 79668 in words is "seventy-nine thousand, six hundred sixty-eight".