81801463 has 2 divisors, whose sum is σ = 81801464. Its totient is φ = 81801462.

The previous prime is 81801449. The next prime is 81801481. The reversal of 81801463 is 36410818.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81801463 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81801163) 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, 40900731 + 40900732.

It is an arithmetic number, because the mean of its divisors is an integer number (40900732).

Almost surely, 2^81801463 is an apocalyptic number.

81801463 is a deficient number, since it is larger than the sum of its proper divisors (1).

81801463 is an equidigital number, since it uses as much as digits as its factorization.

81801463 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 81801463 is about 9044.4161226693. The cubic root of 81801463 is about 434.0972390723.

The spelling of 81801463 in words is "eighty-one million, eight hundred one thousand, four hundred sixty-three".