721045243 has 2 divisors, whose sum is σ = 721045244. Its totient is φ = 721045242.

The previous prime is 721045211. The next prime is 721045253. The reversal of 721045243 is 342540127.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 721045243 - 2⁵ = 721045211 is a prime.

It is not a weakly prime, because it can be changed into another prime (721045253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360522621 + 360522622.

It is an arithmetic number, because the mean of its divisors is an integer number (360522622).

Almost surely, 2^721045243 is an apocalyptic number.

721045243 is a deficient number, since it is larger than the sum of its proper divisors (1).

721045243 is an equidigital number, since it uses as much as digits as its factorization.

721045243 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6720, while the sum is 28.

The square root of 721045243 is about 26852.2856196637. The cubic root of 721045243 is about 896.7144578358.

The spelling of 721045243 in words is "seven hundred twenty-one million, forty-five thousand, two hundred forty-three".