289999999891 has 16 divisors (see below), whose sum is σ = 369394076160. Its totient is φ = 221636442240.

The previous prime is 289999999879. The next prime is 289999999897. The reversal of 289999999891 is 198999999982.

It is a cyclic number.

It is not a de Polignac number, because 289999999891 - 2⁹ = 289999999379 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 289999999796 and 289999999805.

It is not an unprimeable number, because it can be changed into a prime (289999999897) 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, 64128655 + ... + 64133176.

It is an arithmetic number, because the mean of its divisors is an integer number (23087129760).

Almost surely, 2^289999999891 is an apocalyptic number.

289999999891 is a deficient number, since it is larger than the sum of its proper divisors (79394076269).

289999999891 is a wasteful number, since it uses less digits than its factorization.

289999999891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128261874.

The product of its digits is 5509980288, while the sum is 91.

Adding to 289999999891 its sum of digits (91), we get a palindrome (289999999982).

Subtracting from 289999999891 its reverse (198999999982), we obtain a palindrome (90999999909).

The spelling of 289999999891 in words is "two hundred eighty-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, eight hundred ninety-one".