9664451561 has 8 divisors (see below), whose sum is σ = 9682897224. Its totient is φ = 9646024320.

The previous prime is 9664451551. The next prime is 9664451569. The reversal of 9664451561 is 1651544669.

9664451561 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 5532533161 + 4131918400 = 74381^2 + 64280^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-9664451561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9664451569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1447571 + ... + 1454231.

It is an arithmetic number, because the mean of its divisors is an integer number (1210362153).

Almost surely, 2^9664451561 is an apocalyptic number.

It is an amenable number.

9664451561 is a deficient number, since it is larger than the sum of its proper divisors (18445663).

9664451561 is a wasteful number, since it uses less digits than its factorization.

9664451561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9211.

The product of its digits is 777600, while the sum is 47.

The square root of 9664451561 is about 98307.9425122914. The cubic root of 9664451561 is about 2130.0627841192.

The spelling of 9664451561 in words is "nine billion, six hundred sixty-four million, four hundred fifty-one thousand, five hundred sixty-one".