71372611721 has 2 divisors, whose sum is σ = 71372611722. Its totient is φ = 71372611720.

The previous prime is 71372611649. The next prime is 71372611801. The reversal of 71372611721 is 12711627317.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 43695631225 + 27676980496 = 209035^2 + 166364^2 .

It is a cyclic number.

It is not a de Polignac number, because 71372611721 - 2¹⁰ = 71372610697 is a prime.

It is not a weakly prime, because it can be changed into another prime (71392611721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35686305860 + 35686305861.

It is an arithmetic number, because the mean of its divisors is an integer number (35686305861).

Almost surely, 2^71372611721 is an apocalyptic number.

It is an amenable number.

71372611721 is a deficient number, since it is larger than the sum of its proper divisors (1).

71372611721 is an equidigital number, since it uses as much as digits as its factorization.

71372611721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 24696, while the sum is 38.

The spelling of 71372611721 in words is "seventy-one billion, three hundred seventy-two million, six hundred eleven thousand, seven hundred twenty-one".