81118768 has 40 divisors (see below), whose sum is σ = 160580000. Its totient is φ = 39688704.

The previous prime is 81118759. The next prime is 81118777. The reversal of 81118768 is 86781118.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (81118759) and next prime (81118777).

It is a self number, because there is not a number n which added to its sum of digits gives 81118768.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 232258 + ... + 232606.

It is an arithmetic number, because the mean of its divisors is an integer number (4014500).

Almost surely, 2^81118768 is an apocalyptic number.

It is an amenable number.

81118768 is a deficient number, since it is larger than the sum of its proper divisors (79461232).

81118768 is a wasteful number, since it uses less digits than its factorization.

81118768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 629 (or 623 counting only the distinct ones).

The product of its digits is 21504, while the sum is 40.

The square root of 81118768 is about 9006.5958052974. The cubic root of 81118768 is about 432.8862407766.

The spelling of 81118768 in words is "eighty-one million, one hundred eighteen thousand, seven hundred sixty-eight".