11818221 has 8 divisors (see below), whose sum is σ = 15935040. Its totient is φ = 7790112.

The previous prime is 11818217. The next prime is 11818229. The reversal of 11818221 is 12281811.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 11818221 - 2² = 11818217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 11818191 and 11818200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11818229) 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 7 ways as a sum of consecutive naturals, for example, 21865 + ... + 22398.

It is an arithmetic number, because the mean of its divisors is an integer number (1991880).

Almost surely, 2^11818221 is an apocalyptic number.

It is an amenable number.

11818221 is a deficient number, since it is larger than the sum of its proper divisors (4116819).

11818221 is an equidigital number, since it uses as much as digits as its factorization.

11818221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44355.

The product of its digits is 256, while the sum is 24.

The square root of 11818221 is about 3437.7639535023. The cubic root of 11818221 is about 227.7809337831.

The spelling of 11818221 in words is "eleven million, eight hundred eighteen thousand, two hundred twenty-one".