81267271 has 2 divisors, whose sum is σ = 81267272. Its totient is φ = 81267270.

The previous prime is 81267247. The next prime is 81267287. The reversal of 81267271 is 17276218.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81267271 - 2¹⁷ = 81136199 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81207271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40633635 + 40633636.

It is an arithmetic number, because the mean of its divisors is an integer number (40633636).

Almost surely, 2^81267271 is an apocalyptic number.

81267271 is a deficient number, since it is larger than the sum of its proper divisors (1).

81267271 is an equidigital number, since it uses as much as digits as its factorization.

81267271 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9408, while the sum is 34.

The square root of 81267271 is about 9014.8361604635. The cubic root of 81267271 is about 433.1502393487.

The spelling of 81267271 in words is "eighty-one million, two hundred sixty-seven thousand, two hundred seventy-one".