81013071 has 4 divisors (see below), whose sum is σ = 108017432. Its totient is φ = 54008712.

The previous prime is 81013069. The next prime is 81013087. The reversal of 81013071 is 17031018.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 81013071 - 2¹ = 81013069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81013271) 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 in 3 ways as a sum of consecutive naturals, for example, 13502176 + ... + 13502181.

It is an arithmetic number, because the mean of its divisors is an integer number (27004358).

Almost surely, 2^81013071 is an apocalyptic number.

81013071 is a deficient number, since it is larger than the sum of its proper divisors (27004361).

81013071 is a wasteful number, since it uses less digits than its factorization.

81013071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27004360.

The product of its (nonzero) digits is 168, while the sum is 21.

The square root of 81013071 is about 9000.7261373736. The cubic root of 81013071 is about 432.6981434752.

Adding to 81013071 its reverse (17031018), we get a palindrome (98044089).

The spelling of 81013071 in words is "eighty-one million, thirteen thousand, seventy-one".