81418297 has 2 divisors, whose sum is σ = 81418298. Its totient is φ = 81418296.

The previous prime is 81418291. The next prime is 81418301. The reversal of 81418297 is 79281418.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51998521 + 29419776 = 7211^2 + 5424^2 .

It is a cyclic number.

It is not a de Polignac number, because 81418297 - 2²³ = 73029689 is a prime.

It is not a weakly prime, because it can be changed into another prime (81418291) 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, 40709148 + 40709149.

It is an arithmetic number, because the mean of its divisors is an integer number (40709149).

Almost surely, 2^81418297 is an apocalyptic number.

It is an amenable number.

81418297 is a deficient number, since it is larger than the sum of its proper divisors (1).

81418297 is an equidigital number, since it uses as much as digits as its factorization.

81418297 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 40.

The square root of 81418297 is about 9023.2087973182. The cubic root of 81418297 is about 433.4183934929.

The spelling of 81418297 in words is "eighty-one million, four hundred eighteen thousand, two hundred ninety-seven".