71721236273 has 2 divisors, whose sum is σ = 71721236274. Its totient is φ = 71721236272.

The previous prime is 71721236221. The next prime is 71721236359. The reversal of 71721236273 is 37263212717.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 71477626609 + 243609664 = 267353^2 + 15608^2 .

It is a cyclic number.

It is not a de Polignac number, because 71721236273 - 2⁸ = 71721236017 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 71721236273.

It is not a weakly prime, because it can be changed into another prime (71721436273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35860618136 + 35860618137.

It is an arithmetic number, because the mean of its divisors is an integer number (35860618137).

Almost surely, 2^71721236273 is an apocalyptic number.

It is an amenable number.

71721236273 is a deficient number, since it is larger than the sum of its proper divisors (1).

71721236273 is an equidigital number, since it uses as much as digits as its factorization.

71721236273 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 148176, while the sum is 41.

The spelling of 71721236273 in words is "seventy-one billion, seven hundred twenty-one million, two hundred thirty-six thousand, two hundred seventy-three".