9865818161889 has 16 divisors (see below), whose sum is σ = 13928280640128. Its totient is φ = 6190287604992.

The previous prime is 9865818161831. The next prime is 9865818161891. The reversal of 9865818161889 is 9881618185689.

It is not a de Polignac number, because 9865818161889 - 2¹⁵ = 9865818129121 is a prime.

It is a super-2 number, since 2×9865818161889² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (9865818161389) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15859644 + ... + 16469970.

It is an arithmetic number, because the mean of its divisors is an integer number (870517540008).

Almost surely, 2^{9865818161889} is an apocalyptic number.

It is an amenable number.

9865818161889 is a deficient number, since it is larger than the sum of its proper divisors (4062462478239).

9865818161889 is a wasteful number, since it uses less digits than its factorization.

9865818161889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 927304.

The product of its digits is 477757440, while the sum is 78.

The spelling of 9865818161889 in words is "nine trillion, eight hundred sixty-five billion, eight hundred eighteen million, one hundred sixty-one thousand, eight hundred eighty-nine".