11155921 has 4 divisors (see below), whose sum is σ = 12749632. Its totient is φ = 9562212.

The previous prime is 11155891. The next prime is 11155931. The reversal of 11155921 is 12955111.

It is a happy number.

11155921 is digitally balanced in base 2, 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 a cyclic number.

It is not a de Polignac number, because 11155921 - 2⁵ = 11155889 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11155931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 796845 + ... + 796858.

It is an arithmetic number, because the mean of its divisors is an integer number (3187408).

Almost surely, 2^11155921 is an apocalyptic number.

It is an amenable number.

11155921 is a deficient number, since it is larger than the sum of its proper divisors (1593711).

11155921 is an equidigital number, since it uses as much as digits as its factorization.

11155921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1593710.

The product of its digits is 450, while the sum is 25.

The square root of 11155921 is about 3340.0480535465. The cubic root of 11155921 is about 223.4438865047.

The spelling of 11155921 in words is "eleven million, one hundred fifty-five thousand, nine hundred twenty-one".