81271241 has 2 divisors, whose sum is σ = 81271242. Its totient is φ = 81271240.

The previous prime is 81271231. The next prime is 81271297. The reversal of 81271241 is 14217218.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 70896400 + 10374841 = 8420^2 + 3221^2 .

It is a cyclic number.

It is not a de Polignac number, because 81271241 - 2¹⁴ = 81254857 is a prime.

It is a super-2 number, since 2×81271241² = 13210029227360162, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81271241.

It is not a weakly prime, because it can be changed into another prime (81271231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40635620 + 40635621.

It is an arithmetic number, because the mean of its divisors is an integer number (40635621).

Almost surely, 2^81271241 is an apocalyptic number.

It is an amenable number.

81271241 is a deficient number, since it is larger than the sum of its proper divisors (1).

81271241 is an equidigital number, since it uses as much as digits as its factorization.

81271241 is an evil number, because the sum of its binary digits is even.

The product of its digits is 896, while the sum is 26.

The square root of 81271241 is about 9015.0563503508. The cubic root of 81271241 is about 433.1572925303.

Adding to 81271241 its reverse (14217218), we get a palindrome (95488459).

The spelling of 81271241 in words is "eighty-one million, two hundred seventy-one thousand, two hundred forty-one".