9728181 has 20 divisors (see below), whose sum is σ = 14717472. Its totient is φ = 6402888.

The previous prime is 9728177. The next prime is 9728197. The reversal of 9728181 is 1818279.

It is not a de Polignac number, because 9728181 - 2² = 9728177 is a prime.

It is a super-2 number, since 2×9728181² = 189275011137522, which contains 22 as substring.

9728181 is a modest number, since divided by 8181 gives 972 as remainder.

It is a Curzon number.

9728181 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9728281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 6000 + ... + 7446.

Almost surely, 2^9728181 is an apocalyptic number.

It is an amenable number.

9728181 is a deficient number, since it is larger than the sum of its proper divisors (4989291).

9728181 is a wasteful number, since it uses less digits than its factorization.

9728181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1542 (or 1533 counting only the distinct ones).

The product of its digits is 8064, while the sum is 36.

The square root of 9728181 is about 3119.0032061542. The cubic root of 9728181 is about 213.4734558498.

The spelling of 9728181 in words is "nine million, seven hundred twenty-eight thousand, one hundred eighty-one".