81885863 has 2 divisors, whose sum is σ = 81885864. Its totient is φ = 81885862.

The previous prime is 81885857. The next prime is 81885887. The reversal of 81885863 is 36858818.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81885863 - 2⁶ = 81885799 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81885163) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40942931 + 40942932.

It is an arithmetic number, because the mean of its divisors is an integer number (40942932).

Almost surely, 2^81885863 is an apocalyptic number.

81885863 is a deficient number, since it is larger than the sum of its proper divisors (1).

81885863 is an equidigital number, since it uses as much as digits as its factorization.

81885863 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 368640, while the sum is 47.

The square root of 81885863 is about 9049.0807820463. The cubic root of 81885863 is about 434.2464834024.

The spelling of 81885863 in words is "eighty-one million, eight hundred eighty-five thousand, eight hundred sixty-three".