81301663 has 2 divisors, whose sum is σ = 81301664. Its totient is φ = 81301662.

The previous prime is 81301651. The next prime is 81301669. The reversal of 81301663 is 36610318.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81301663 - 2⁵ = 81301631 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81301669) 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, 40650831 + 40650832.

It is an arithmetic number, because the mean of its divisors is an integer number (40650832).

Almost surely, 2^81301663 is an apocalyptic number.

81301663 is a deficient number, since it is larger than the sum of its proper divisors (1).

81301663 is an equidigital number, since it uses as much as digits as its factorization.

81301663 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 81301663 is about 9016.7434808804. The cubic root of 81301663 is about 433.2113332426.

The spelling of 81301663 in words is "eighty-one million, three hundred one thousand, six hundred sixty-three".