81205063 has 8 divisors (see below), whose sum is σ = 84142800. Its totient is φ = 78319488.

The previous prime is 81205037. The next prime is 81205079. The reversal of 81205063 is 36050218.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81205063 - 2⁹ = 81204551 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81205013) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9858 + ... + 16111.

It is an arithmetic number, because the mean of its divisors is an integer number (10517850).

Almost surely, 2^81205063 is an apocalyptic number.

81205063 is a deficient number, since it is larger than the sum of its proper divisors (2937737).

81205063 is a wasteful number, since it uses less digits than its factorization.

81205063 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26081.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 81205063 is about 9011.3851876390. The cubic root of 81205063 is about 433.0396893572.

The spelling of 81205063 in words is "eighty-one million, two hundred five thousand, sixty-three".