81017168 has 20 divisors (see below), whose sum is σ = 157201620. Its totient is φ = 40449024.

The previous prime is 81017119. The next prime is 81017171. The reversal of 81017168 is 86171018.

It can be written as a sum of positive squares in 2 ways, for example, as 59413264 + 21603904 = 7708^2 + 4648^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8768 + ... + 15456.

It is an arithmetic number, because the mean of its divisors is an integer number (7860081).

Almost surely, 2^81017168 is an apocalyptic number.

It is an amenable number.

81017168 is a deficient number, since it is larger than the sum of its proper divisors (76184452).

81017168 is a wasteful number, since it uses less digits than its factorization.

81017168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7454 (or 7448 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 32.

The square root of 81017168 is about 9000.9537272447. The cubic root of 81017168 is about 432.7054375015.

The spelling of 81017168 in words is "eighty-one million, seventeen thousand, one hundred sixty-eight".