1189890 has 80 divisors (see below), whose sum is σ = 3476088. Its totient is φ = 290304.

The previous prime is 1189879. The next prime is 1189891. The reversal of 1189890 is 989811.

It can be written as a sum of positive squares in 4 ways, for example, as 363609 + 826281 = 603^2 + 909^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1189891) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 10474 + ... + 10586.

2^1189890 is an apocalyptic number.

1189890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1189890, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1738044).

1189890 is an abundant number, since it is smaller than the sum of its proper divisors (2286198).

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

1189890 is a wasteful number, since it uses less digits than its factorization.

1189890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145 (or 136 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 36.

The square root of 1189890 is about 1090.8207918810. The cubic root of 1189890 is about 105.9665849344.

The spelling of 1189890 in words is "one million, one hundred eighty-nine thousand, eight hundred ninety".