721080730709 has 4 divisors (see below), whose sum is σ = 721092528300. Its totient is φ = 721068933120.

The previous prime is 721080730697. The next prime is 721080730819. The reversal of 721080730709 is 907037080127.

721080730709 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 907037080127 = 170633 ⋅5315719.

It can be written as a sum of positive squares in 2 ways, for example, as 362223422500 + 358857308209 = 601850^2 + 599047^2 .

It is a cyclic number.

It is not a de Polignac number, because 721080730709 - 2²⁰ = 721079682133 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 721080730709.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721080730309) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5806634 + ... + 5929515.

It is an arithmetic number, because the mean of its divisors is an integer number (180273132075).

Almost surely, 2^721080730709 is an apocalyptic number.

It is an amenable number.

721080730709 is a deficient number, since it is larger than the sum of its proper divisors (11797591).

721080730709 is a wasteful number, since it uses less digits than its factorization.

721080730709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11797590.

The product of its (nonzero) digits is 148176, while the sum is 44.

The spelling of 721080730709 in words is "seven hundred twenty-one billion, eighty million, seven hundred thirty thousand, seven hundred nine".