721225986791 has 2 divisors, whose sum is σ = 721225986792. Its totient is φ = 721225986790.

The previous prime is 721225986763. The next prime is 721225986827. The reversal of 721225986791 is 197689522127.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 721225986791 - 2³⁰ = 720152244967 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 721225986791.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (721225986491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360612993395 + 360612993396.

It is an arithmetic number, because the mean of its divisors is an integer number (360612993396).

Almost surely, 2^721225986791 is an apocalyptic number.

721225986791 is a deficient number, since it is larger than the sum of its proper divisors (1).

721225986791 is an equidigital number, since it uses as much as digits as its factorization.

721225986791 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7620480, while the sum is 59.

The spelling of 721225986791 in words is "seven hundred twenty-one billion, two hundred twenty-five million, nine hundred eighty-six thousand, seven hundred ninety-one".