81288871 has 2 divisors, whose sum is σ = 81288872. Its totient is φ = 81288870.

The previous prime is 81288853. The next prime is 81288881. The reversal of 81288871 is 17888218.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81288871 - 2⁵ = 81288839 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81288811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40644435 + 40644436.

It is an arithmetic number, because the mean of its divisors is an integer number (40644436).

Almost surely, 2^81288871 is an apocalyptic number.

81288871 is a deficient number, since it is larger than the sum of its proper divisors (1).

81288871 is an equidigital number, since it uses as much as digits as its factorization.

81288871 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 57344, while the sum is 43.

The square root of 81288871 is about 9016.0341059692. The cubic root of 81288871 is about 433.1886115670.

The spelling of 81288871 in words is "eighty-one million, two hundred eighty-eight thousand, eight hundred seventy-one".