9865881 has 15 divisors (see below), whose sum is σ = 14780271.
Its totient is φ = 6558408.
The previous prime is 9865879. The next prime is 9865903. The reversal of 9865881 is 1885689.
The square root of 9865881 is 3141.
It is a perfect power (a square), and thus also a powerful number.
It can be written as a sum of positive squares in only one way, i.e., 7241481 + 2624400 = 2691^2 + 1620^2
It is not a de Polignac number, because 9865881 - 21 = 9865879 is a prime.
It is a super-2 number, since 2×98658812 = 194671215812322, which contains 22 as substring.
It is not an unprimeable number, because it can be changed into a prime (9865811) 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 14 ways as a sum of consecutive naturals, for example, 28095 + ... + 28443.
Almost surely, 29865881 is an apocalyptic number.
9865881 is the 3141-st square number.
9865881 is the 1571-st centered octagonal number.
It is an amenable number.
9865881 is a deficient number, since it is larger than the sum of its proper divisors (4914390).
9865881 is an frugal number, since it uses more digits than its factorization.
9865881 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 710 (or 352 counting only the distinct ones).
The product of its digits is 138240, while the sum is 45.
The cubic root of 9865881 is about 214.4759619011.
The spelling of 9865881 in words is "nine million, eight hundred sixty-five thousand, eight hundred eighty-one".