11145221 has 2 divisors, whose sum is σ = 11145222. Its totient is φ = 11145220.

The previous prime is 11145187. The next prime is 11145223. The reversal of 11145221 is 12254111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5692996 + 5452225 = 2386^2 + 2335^2 .

It is an emirp because it is prime and its reverse (12254111) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11145221 is a prime.

It is a super-2 number, since 2×11145221² = 248431902277682, which contains 22 as substring.

Together with 11145223, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 11145221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11145223) 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 as a sum of consecutive naturals, namely, 5572610 + 5572611.

It is an arithmetic number, because the mean of its divisors is an integer number (5572611).

Almost surely, 2^11145221 is an apocalyptic number.

It is an amenable number.

11145221 is a deficient number, since it is larger than the sum of its proper divisors (1).

11145221 is an equidigital number, since it uses as much as digits as its factorization.

11145221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 80, while the sum is 17.

The square root of 11145221 is about 3338.4458959222. The cubic root of 11145221 is about 223.3724262647.

Adding to 11145221 its reverse (12254111), we get a palindrome (23399332).

The spelling of 11145221 in words is "eleven million, one hundred forty-five thousand, two hundred twenty-one".