81716827 has 2 divisors, whose sum is σ = 81716828. Its totient is φ = 81716826.

The previous prime is 81716749. The next prime is 81716851. The reversal of 81716827 is 72861718.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81716827 - 2⁷ = 81716699 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81716827.

It is not a weakly prime, because it can be changed into another prime (81716897) 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 as a sum of consecutive naturals, namely, 40858413 + 40858414.

It is an arithmetic number, because the mean of its divisors is an integer number (40858414).

Almost surely, 2^81716827 is an apocalyptic number.

81716827 is a deficient number, since it is larger than the sum of its proper divisors (1).

81716827 is an equidigital number, since it uses as much as digits as its factorization.

81716827 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 37632, while the sum is 40.

The square root of 81716827 is about 9039.7360027824. The cubic root of 81716827 is about 433.9474743004.

The spelling of 81716827 in words is "eighty-one million, seven hundred sixteen thousand, eight hundred twenty-seven".