9901181844 has 36 divisors (see below), whose sum is σ = 25370843316. Its totient is φ = 3255182208.

The previous prime is 9901181839. The next prime is 9901181863. The reversal of 9901181844 is 4481811099.

It can be written as a sum of positive squares in 2 ways, for example, as 1725405444 + 8175776400 = 41538^2 + 90420^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a self number, because there is not a number n which added to its sum of digits gives 9901181844.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1881159 + ... + 1886414.

Almost surely, 2^9901181844 is an apocalyptic number.

It is an amenable number.

9901181844 is an abundant number, since it is smaller than the sum of its proper divisors (15469661472).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9901181844 is a wasteful number, since it uses less digits than its factorization.

9901181844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3767656 (or 3767651 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 45.

The square root of 9901181844 is about 99504.6825229848. The cubic root of 9901181844 is about 2147.3146097238.

The spelling of 9901181844 in words is "nine billion, nine hundred one million, one hundred eighty-one thousand, eight hundred forty-four".