11218021 has 4 divisors (see below), whose sum is σ = 11248000. Its totient is φ = 11188044.

The previous prime is 11218013. The next prime is 11218049. The reversal of 11218021 is 12081211.

11218021 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, and also an emirpimes, since its reverse is a distinct semiprime: 12081211 = 239 ⋅50549.

It is a cyclic number.

It is not a de Polignac number, because 11218021 - 2³ = 11218013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11217986 and 11218004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11248021) 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, 14421 + ... + 15178.

It is an arithmetic number, because the mean of its divisors is an integer number (2812000).

Almost surely, 2^11218021 is an apocalyptic number.

It is an amenable number.

11218021 is a deficient number, since it is larger than the sum of its proper divisors (29979).

11218021 is an equidigital number, since it uses as much as digits as its factorization.

11218021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29978.

The product of its (nonzero) digits is 32, while the sum is 16.

The square root of 11218021 is about 3349.3314258222. The cubic root of 11218021 is about 223.8577234790.

Adding to 11218021 its reverse (12081211), we get a palindrome (23299232).

The spelling of 11218021 in words is "eleven million, two hundred eighteen thousand, twenty-one".