71327581 has 4 divisors (see below), whose sum is σ = 76814332. Its totient is φ = 65840832.

The previous prime is 71327569. The next prime is 71327587. The reversal of 71327581 is 18572317.

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

It can be written as a sum of positive squares in 2 ways, for example, as 26316900 + 45010681 = 5130^2 + 6709^2 .

It is a cyclic number.

It is not a de Polignac number, because 71327581 - 2⁵ = 71327549 is a prime.

It is a super-2 number, since 2×71327581² = 10175247622623122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71327587) 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, 2743356 + ... + 2743381.

It is an arithmetic number, because the mean of its divisors is an integer number (19203583).

Almost surely, 2^71327581 is an apocalyptic number.

It is an amenable number.

71327581 is a deficient number, since it is larger than the sum of its proper divisors (5486751).

71327581 is a wasteful number, since it uses less digits than its factorization.

71327581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5486750.

The product of its digits is 11760, while the sum is 34.

The square root of 71327581 is about 8445.5657596161. The cubic root of 71327581 is about 414.7176305328.

Adding to 71327581 its reverse (18572317), we get a palindrome (89899898).

The spelling of 71327581 in words is "seventy-one million, three hundred twenty-seven thousand, five hundred eighty-one".