71281131421 has 32 divisors (see below), whose sum is σ = 79710220800. Its totient is φ = 63501419520.

The previous prime is 71281131419. The next prime is 71281131463. The reversal of 71281131421 is 12413118217.

It is a cyclic number.

It is not a de Polignac number, because 71281131421 - 2¹ = 71281131419 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 (71281131401) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2419240 + ... + 2448526.

It is an arithmetic number, because the mean of its divisors is an integer number (2490944400).

Almost surely, 2^71281131421 is an apocalyptic number.

It is an amenable number.

71281131421 is a deficient number, since it is larger than the sum of its proper divisors (8429089379).

71281131421 is a wasteful number, since it uses less digits than its factorization.

71281131421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29469.

The product of its digits is 2688, while the sum is 31.

Adding to 71281131421 its reverse (12413118217), we get a palindrome (83694249638).

The spelling of 71281131421 in words is "seventy-one billion, two hundred eighty-one million, one hundred thirty-one thousand, four hundred twenty-one".