81011263 has 2 divisors, whose sum is σ = 81011264. Its totient is φ = 81011262.

The previous prime is 81011219. The next prime is 81011279. The reversal of 81011263 is 36211018.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81011263 - 2¹³ = 81003071 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81011363) 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, 40505631 + 40505632.

It is an arithmetic number, because the mean of its divisors is an integer number (40505632).

Almost surely, 2^81011263 is an apocalyptic number.

81011263 is a deficient number, since it is larger than the sum of its proper divisors (1).

81011263 is an equidigital number, since it uses as much as digits as its factorization.

81011263 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 22.

The square root of 81011263 is about 9000.6257004722. The cubic root of 81011263 is about 432.6949245540.

The spelling of 81011263 in words is "eighty-one million, eleven thousand, two hundred sixty-three".