9720049561 has 2 divisors, whose sum is σ = 9720049562. Its totient is φ = 9720049560.

The previous prime is 9720049553. The next prime is 9720049601. The reversal of 9720049561 is 1659400279.

It is a happy number.

9720049561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5770681225 + 3949368336 = 75965^2 + 62844^2 .

It is a cyclic number.

It is not a de Polignac number, because 9720049561 - 2³ = 9720049553 is a prime.

It is not a weakly prime, because it can be changed into another prime (9720049501) 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, 4860024780 + 4860024781.

It is an arithmetic number, because the mean of its divisors is an integer number (4860024781).

Almost surely, 2^9720049561 is an apocalyptic number.

It is an amenable number.

9720049561 is a deficient number, since it is larger than the sum of its proper divisors (1).

9720049561 is an equidigital number, since it uses as much as digits as its factorization.

9720049561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 136080, while the sum is 43.

The square root of 9720049561 is about 98590.3116994768. The cubic root of 9720049561 is about 2134.1396099140.

The spelling of 9720049561 in words is "nine billion, seven hundred twenty million, forty-nine thousand, five hundred sixty-one".