1188889 has 4 divisors (see below), whose sum is σ = 1280356. Its totient is φ = 1097424.

The previous prime is 1188857. The next prime is 1188899. The reversal of 1188889 is 9888811.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9888811 = 2003 ⋅4937.

It can be written as a sum of positive squares in 2 ways, for example, as 267289 + 921600 = 517^2 + 960^2 .

It is a cyclic number.

It is not a de Polignac number, because 1188889 - 2⁵ = 1188857 is a prime.

It is a Duffinian number.

1188889 is a lucky number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (1188839) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45714 + ... + 45739.

It is an arithmetic number, because the mean of its divisors is an integer number (320089).

2^1188889 is an apocalyptic number.

It is an amenable number.

1188889 is a deficient number, since it is larger than the sum of its proper divisors (91467).

1188889 is an equidigital number, since it uses as much as digits as its factorization.

1188889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91466.

The product of its digits is 36864, while the sum is 43.

The square root of 1188889 is about 1090.3618665379. The cubic root of 1188889 is about 105.9368616518.

It can be divided in two parts, 11 and 88889, that multiplied together give a palindrome (977779).

The spelling of 1188889 in words is "one million, one hundred eighty-eight thousand, eight hundred eighty-nine".