79881728 has 20 divisors (see below), whose sum is σ = 159608460. Its totient is φ = 39940608.

The previous prime is 79881721. The next prime is 79881733. The reversal of 79881728 is 82718897.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (79881721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77498 + ... + 78521.

It is an arithmetic number, because the mean of its divisors is an integer number (7980423).

Almost surely, 2^79881728 is an apocalyptic number.

It is an amenable number.

79881728 is a deficient number, since it is larger than the sum of its proper divisors (79726732).

79881728 is an equidigital number, since it uses as much as digits as its factorization.

79881728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156037 (or 156021 counting only the distinct ones).

The product of its digits is 451584, while the sum is 50.

The square root of 79881728 is about 8937.6578587458. The cubic root of 79881728 is about 430.6744921956.

The spelling of 79881728 in words is "seventy-nine million, eight hundred eighty-one thousand, seven hundred twenty-eight".