71721169453 has 4 divisors (see below), whose sum is σ = 71827109820. Its totient is φ = 71615229088.

The previous prime is 71721169451. The next prime is 71721169459. The reversal of 71721169453 is 35496112717.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 35496112717 = 13 ⋅2730470209.

It can be written as a sum of positive squares in 2 ways, for example, as 59302964484 + 12418204969 = 243522^2 + 111437^2 .

It is a cyclic number.

It is not a de Polignac number, because 71721169453 - 2¹ = 71721169451 is a prime.

It is a super-2 number, since 2×71721169453² (a number of 23 digits) 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 (71721169451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 52969168 + ... + 52970521.

It is an arithmetic number, because the mean of its divisors is an integer number (17956777455).

Almost surely, 2^71721169453 is an apocalyptic number.

It is an amenable number.

71721169453 is a deficient number, since it is larger than the sum of its proper divisors (105940367).

71721169453 is a wasteful number, since it uses less digits than its factorization.

71721169453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105940366.

The product of its digits is 317520, while the sum is 46.

The spelling of 71721169453 in words is "seventy-one billion, seven hundred twenty-one million, one hundred sixty-nine thousand, four hundred fifty-three".