81317068 has 30 divisors (see below), whose sum is σ = 166032076. Its totient is φ = 34846056.

The previous prime is 81317057. The next prime is 81317077. The reversal of 81317068 is 86071318.

It is a super-2 number, since 2×81317068² = 13224931096233248, which contains 22 as substring.

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 5371 + ... + 13837.

Almost surely, 2^81317068 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81317068, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83016038).

81317068 is an abundant number, since it is smaller than the sum of its proper divisors (84715008).

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

81317068 is an equidigital number, since it uses as much as digits as its factorization.

81317068 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8499 (or 8476 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 81317068 is about 9017.5976845277. The cubic root of 81317068 is about 433.2386930730.

The spelling of 81317068 in words is "eighty-one million, three hundred seventeen thousand, sixty-eight".