726209215691 has 2 divisors, whose sum is σ = 726209215692. Its totient is φ = 726209215690.

The previous prime is 726209215619. The next prime is 726209215741. The reversal of 726209215691 is 196512902627.

726209215691 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with previous prime (726209215619) it forms an Ormiston pair, because they use the same digits, order apart.

It is an a-pointer prime, because the next prime (726209215741) can be obtained adding 726209215691 to its sum of digits (50).

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-726209215691 is a prime.

It is not a weakly prime, because it can be changed into another prime (726209215891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 363104607845 + 363104607846.

It is an arithmetic number, because the mean of its divisors is an integer number (363104607846).

Almost surely, 2^726209215691 is an apocalyptic number.

726209215691 is a deficient number, since it is larger than the sum of its proper divisors (1).

726209215691 is an equidigital number, since it uses as much as digits as its factorization.

726209215691 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 816480, while the sum is 50.

The spelling of 726209215691 in words is "seven hundred twenty-six billion, two hundred nine million, two hundred fifteen thousand, six hundred ninety-one".