81122317 has 8 divisors (see below), whose sum is σ = 85995000. Its totient is φ = 76260864.

The previous prime is 81122299. The next prime is 81122323. The reversal of 81122317 is 71322118.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 49829481 + 31292836 = 7059^2 + 5594^2 .

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 81122317 - 2²³ = 72733709 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81122291 and 81122300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81122347) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 15559 + ... + 20107.

It is an arithmetic number, because the mean of its divisors is an integer number (10749375).

Almost surely, 2^81122317 is an apocalyptic number.

It is an amenable number.

81122317 is a deficient number, since it is larger than the sum of its proper divisors (4872683).

81122317 is a wasteful number, since it uses less digits than its factorization.

81122317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5615.

The product of its digits is 672, while the sum is 25.

The square root of 81122317 is about 9006.7928254179. The cubic root of 81122317 is about 432.8925537048.

The spelling of 81122317 in words is "eighty-one million, one hundred twenty-two thousand, three hundred seventeen".