724243561 has 2 divisors, whose sum is σ = 724243562. Its totient is φ = 724243560.

The previous prime is 724243549. The next prime is 724243591. The reversal of 724243561 is 165342427.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 564347536 + 159896025 = 23756^2 + 12645^2 .

It is a cyclic number.

It is not a de Polignac number, because 724243561 - 2⁵ = 724243529 is a prime.

It is not a weakly prime, because it can be changed into another prime (724243591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 362121780 + 362121781.

It is an arithmetic number, because the mean of its divisors is an integer number (362121781).

Almost surely, 2^724243561 is an apocalyptic number.

It is an amenable number.

724243561 is a deficient number, since it is larger than the sum of its proper divisors (1).

724243561 is an equidigital number, since it uses as much as digits as its factorization.

724243561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 40320, while the sum is 34.

The square root of 724243561 is about 26911.7736502074. The cubic root of 724243561 is about 898.0383451466.

Adding to 724243561 its reverse (165342427), we get a palindrome (889585988).

The spelling of 724243561 in words is "seven hundred twenty-four million, two hundred forty-three thousand, five hundred sixty-one".