81441313 has 2 divisors, whose sum is σ = 81441314. Its totient is φ = 81441312.

The previous prime is 81441289. The next prime is 81441361. The reversal of 81441313 is 31314418.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 56670784 + 24770529 = 7528^2 + 4977^2 .

It is a cyclic number.

It is not a de Polignac number, because 81441313 - 2⁵ = 81441281 is a prime.

It is not a weakly prime, because it can be changed into another prime (81441383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40720656 + 40720657.

It is an arithmetic number, because the mean of its divisors is an integer number (40720657).

Almost surely, 2^81441313 is an apocalyptic number.

It is an amenable number.

81441313 is a deficient number, since it is larger than the sum of its proper divisors (1).

81441313 is an equidigital number, since it uses as much as digits as its factorization.

81441313 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 25.

The square root of 81441313 is about 9024.4840849768. The cubic root of 81441313 is about 433.4592304148.

The spelling of 81441313 in words is "eighty-one million, four hundred forty-one thousand, three hundred thirteen".