9901129561 has 8 divisors (see below), whose sum is σ = 10134527040. Its totient is φ = 9667874832.

The previous prime is 9901129549. The next prime is 9901129571. The reversal of 9901129561 is 1659211099.

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

It is a cyclic number.

It is not a de Polignac number, because 9901129561 - 2²⁹ = 9364258649 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a pancake number, because a pancake can be divided into 9901129561 parts by 140720 straight cuts.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9901129531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 111756 + ... + 179698.

It is an arithmetic number, because the mean of its divisors is an integer number (1266815880).

Almost surely, 2^9901129561 is an apocalyptic number.

It is an amenable number.

9901129561 is a deficient number, since it is larger than the sum of its proper divisors (233397479).

9901129561 is a wasteful number, since it uses less digits than its factorization.

9901129561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71375.

The product of its (nonzero) digits is 43740, while the sum is 43.

The square root of 9901129561 is about 99504.4198063584. The cubic root of 9901129561 is about 2147.3108300994.

The spelling of 9901129561 in words is "nine billion, nine hundred one million, one hundred twenty-nine thousand, five hundred sixty-one".