721747441 has 2 divisors, whose sum is σ = 721747442. Its totient is φ = 721747440.

The previous prime is 721747417. The next prime is 721747457. The reversal of 721747441 is 144747127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 475414416 + 246333025 = 21804^2 + 15695^2 .

It is a cyclic number.

It is not a de Polignac number, because 721747441 - 2¹¹ = 721745393 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 721747441.

It is not a weakly prime, because it can be changed into another prime (721747241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 360873720 + 360873721.

It is an arithmetic number, because the mean of its divisors is an integer number (360873721).

Almost surely, 2^721747441 is an apocalyptic number.

It is an amenable number.

721747441 is a deficient number, since it is larger than the sum of its proper divisors (1).

721747441 is an equidigital number, since it uses as much as digits as its factorization.

721747441 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43904, while the sum is 37.

The square root of 721747441 is about 26865.3576376716. The cubic root of 721747441 is about 897.0054552045.

The spelling of 721747441 in words is "seven hundred twenty-one million, seven hundred forty-seven thousand, four hundred forty-one".