72730661 has 2 divisors, whose sum is σ = 72730662. Its totient is φ = 72730660.

The previous prime is 72730633. The next prime is 72730663. The reversal of 72730661 is 16603727.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68790436 + 3940225 = 8294^2 + 1985^2 .

It is a cyclic number.

It is not a de Polignac number, because 72730661 - 2¹⁴ = 72714277 is a prime.

Together with 72730663, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72730663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36365330 + 36365331.

It is an arithmetic number, because the mean of its divisors is an integer number (36365331).

Almost surely, 2^72730661 is an apocalyptic number.

It is an amenable number.

72730661 is a deficient number, since it is larger than the sum of its proper divisors (1).

72730661 is an equidigital number, since it uses as much as digits as its factorization.

72730661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10584, while the sum is 32.

The square root of 72730661 is about 8528.2273070082. The cubic root of 72730661 is about 417.4192866309.

The spelling of 72730661 in words is "seventy-two million, seven hundred thirty thousand, six hundred sixty-one".