81444353 has 2 divisors, whose sum is σ = 81444354. Its totient is φ = 81444352.

The previous prime is 81444343. The next prime is 81444361. The reversal of 81444353 is 35344418.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 80856064 + 588289 = 8992^2 + 767^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81444353 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (81444343) 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 as a sum of consecutive naturals, namely, 40722176 + 40722177.

It is an arithmetic number, because the mean of its divisors is an integer number (40722177).

Almost surely, 2^81444353 is an apocalyptic number.

It is an amenable number.

81444353 is a deficient number, since it is larger than the sum of its proper divisors (1).

81444353 is an equidigital number, since it uses as much as digits as its factorization.

81444353 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 23040, while the sum is 32.

The square root of 81444353 is about 9024.6525140861. The cubic root of 81444353 is about 433.4646236630.

The spelling of 81444353 in words is "eighty-one million, four hundred forty-four thousand, three hundred fifty-three".