9981288 has 24 divisors (see below), whose sum is σ = 27032850. Its totient is φ = 3327072.

The previous prime is 9981271. The next prime is 9981317. The reversal of 9981288 is 8821899.

It can be written as a sum of positive squares in only one way, i.e., 8191044 + 1790244 = 2862^2 + 1338^2 .

It is a tau number, because it is divible by the number of its divisors (24).

It is a super-2 number, since 2×9981288² = 199252220277888, which contains 22 as substring.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 69243 + ... + 69386.

Almost surely, 2^9981288 is an apocalyptic number.

It is an amenable number.

9981288 is an abundant number, since it is smaller than the sum of its proper divisors (17051562).

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

9981288 is a wasteful number, since it uses less digits than its factorization.

9981288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138641 (or 138634 counting only the distinct ones).

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

The square root of 9981288 is about 3159.3176478474. The cubic root of 9981288 is about 215.3090058260.

The spelling of 9981288 in words is "nine million, nine hundred eighty-one thousand, two hundred eighty-eight".