81116971 has 8 divisors (see below), whose sum is σ = 89216064. Its totient is φ = 73283520.

The previous prime is 81116953. The next prime is 81116989. The reversal of 81116971 is 17961118.

It is an interprime number because it is at equal distance from previous prime (81116953) and next prime (81116989).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81116971 - 2⁹ = 81116459 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (81116951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 65770 + ... + 66991.

It is an arithmetic number, because the mean of its divisors is an integer number (11152008).

Almost surely, 2^81116971 is an apocalyptic number.

81116971 is a deficient number, since it is larger than the sum of its proper divisors (8099093).

81116971 is a wasteful number, since it uses less digits than its factorization.

81116971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 132821.

The product of its digits is 3024, while the sum is 34.

The square root of 81116971 is about 9006.4960445225. The cubic root of 81116971 is about 432.8830442195.

The spelling of 81116971 in words is "eighty-one million, one hundred sixteen thousand, nine hundred seventy-one".