81360893 has 2 divisors, whose sum is σ = 81360894. Its totient is φ = 81360892.

The previous prime is 81360889. The next prime is 81360911. The reversal of 81360893 is 39806318.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 51308569 + 30052324 = 7163^2 + 5482^2 .

It is a cyclic number.

It is not a de Polignac number, because 81360893 - 2² = 81360889 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81360493) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40680446 + 40680447.

It is an arithmetic number, because the mean of its divisors is an integer number (40680447).

Almost surely, 2^81360893 is an apocalyptic number.

It is an amenable number.

81360893 is a deficient number, since it is larger than the sum of its proper divisors (1).

81360893 is an equidigital number, since it uses as much as digits as its factorization.

81360893 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 81360893 is about 9020.0273281182. The cubic root of 81360893 is about 433.3165089457.

The spelling of 81360893 in words is "eighty-one million, three hundred sixty thousand, eight hundred ninety-three".