72730521013 has 2 divisors, whose sum is σ = 72730521014. Its totient is φ = 72730521012.

The previous prime is 72730521001. The next prime is 72730521067. The reversal of 72730521013 is 31012503727.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 72726223684 + 4297329 = 269678^2 + 2073^2 .

It is a cyclic number.

It is not a de Polignac number, because 72730521013 - 2⁵ = 72730520981 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72730521313) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36365260506 + 36365260507.

It is an arithmetic number, because the mean of its divisors is an integer number (36365260507).

Almost surely, 2^72730521013 is an apocalyptic number.

It is an amenable number.

72730521013 is a deficient number, since it is larger than the sum of its proper divisors (1).

72730521013 is an equidigital number, since it uses as much as digits as its factorization.

72730521013 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8820, while the sum is 31.

The spelling of 72730521013 in words is "seventy-two billion, seven hundred thirty million, five hundred twenty-one thousand, thirteen".