9729132561 has 16 divisors (see below), whose sum is σ = 14527027200. Its totient is φ = 6435014544.

The previous prime is 9729132547. The next prime is 9729132613. The reversal of 9729132561 is 1652319279.

It is a happy number.

9729132561 is a `hidden beast` number, since 9 + 72 + 9 + 13 + 2 + 561 = 666.

It is not a de Polignac number, because 9729132561 - 2²² = 9724938257 is a prime.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (9729132961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1415226 + ... + 1422083.

It is an arithmetic number, because the mean of its divisors is an integer number (907939200).

Almost surely, 2^9729132561 is an apocalyptic number.

It is an amenable number.

9729132561 is a deficient number, since it is larger than the sum of its proper divisors (4797894639).

9729132561 is a wasteful number, since it uses less digits than its factorization.

9729132561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2837445 (or 2837439 counting only the distinct ones).

The product of its digits is 204120, while the sum is 45.

The square root of 9729132561 is about 98636.3653071219. The cubic root of 9729132561 is about 2134.8041591740.

The spelling of 9729132561 in words is "nine billion, seven hundred twenty-nine million, one hundred thirty-two thousand, five hundred sixty-one".