11289981 has 4 divisors (see below), whose sum is σ = 15053312. Its totient is φ = 7526652.

The previous prime is 11289979. The next prime is 11290003. The reversal of 11289981 is 18998211.

11289981 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 11289981 - 2¹ = 11289979 is a prime.

It is a super-2 number, since 2×11289981² = 254927341960722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11289911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1881661 + ... + 1881666.

It is an arithmetic number, because the mean of its divisors is an integer number (3763328).

Almost surely, 2^11289981 is an apocalyptic number.

It is an amenable number.

11289981 is a deficient number, since it is larger than the sum of its proper divisors (3763331).

11289981 is an equidigital number, since it uses as much as digits as its factorization.

11289981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3763330.

The product of its digits is 10368, while the sum is 39.

The square root of 11289981 is about 3360.0566959502. The cubic root of 11289981 is about 224.3353620853.

The spelling of 11289981 in words is "eleven million, two hundred eighty-nine thousand, nine hundred eighty-one".