11221121 has 4 divisors (see below), whose sum is σ = 11228592. Its totient is φ = 11213652.

The previous prime is 11221103. The next prime is 11221123. The reversal of 11221121 is 12112211.

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, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 12112211 = 17 ⋅712483.

It is a cyclic number.

It is not a de Polignac number, because 11221121 - 2¹⁸ = 10958977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11221123) 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, 611 + ... + 4776.

It is an arithmetic number, because the mean of its divisors is an integer number (2807148).

Almost surely, 2^11221121 is an apocalyptic number.

It is an amenable number.

11221121 is a deficient number, since it is larger than the sum of its proper divisors (7471).

11221121 is an equidigital number, since it uses as much as digits as its factorization.

11221121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7470.

The product of its digits is 8, while the sum is 11.

The square root of 11221121 is about 3349.7941727814. The cubic root of 11221121 is about 223.8783419413.

Adding to 11221121 its reverse (12112211), we get a palindrome (23333332).

The spelling of 11221121 in words is "eleven million, two hundred twenty-one thousand, one hundred twenty-one".