9615648561 has 4 divisors (see below), whose sum is σ = 12820864752. Its totient is φ = 6410432372.

The previous prime is 9615648557. The next prime is 9615648629. The reversal of 9615648561 is 1658465169.

9615648561 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1658465169 = 3 ⋅552821723.

It is a cyclic number.

It is not a de Polignac number, because 9615648561 - 2² = 9615648557 is a prime.

It is a super-2 number, since 2×9615648561² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (9615648461) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1602608091 + ... + 1602608096.

It is an arithmetic number, because the mean of its divisors is an integer number (3205216188).

Almost surely, 2^9615648561 is an apocalyptic number.

It is an amenable number.

9615648561 is a deficient number, since it is larger than the sum of its proper divisors (3205216191).

9615648561 is a wasteful number, since it uses less digits than its factorization.

9615648561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3205216190.

The product of its digits is 1555200, while the sum is 51.

The square root of 9615648561 is about 98059.4134236994. The cubic root of 9615648561 is about 2126.4713085152.

The spelling of 9615648561 in words is "nine billion, six hundred fifteen million, six hundred forty-eight thousand, five hundred sixty-one".