11121821 has 8 divisors (see below), whose sum is σ = 11980320. Its totient is φ = 10290672.

The previous prime is 11121767. The next prime is 11121823. The reversal of 11121821 is 12812111.

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

It is a cyclic number.

It is not a de Polignac number, because 11121821 - 2¹⁸ = 10859677 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11121821.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11121823) 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, 5990 + ... + 7623.

It is an arithmetic number, because the mean of its divisors is an integer number (1497540).

Almost surely, 2^11121821 is an apocalyptic number.

It is an amenable number.

11121821 is a deficient number, since it is larger than the sum of its proper divisors (858499).

11121821 is a wasteful number, since it uses less digits than its factorization.

11121821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13675.

The product of its digits is 32, while the sum is 17.

The square root of 11121821 is about 3334.9394297348. The cubic root of 11121821 is about 223.2159891960.

Adding to 11121821 its reverse (12812111), we get a palindrome (23933932).

The spelling of 11121821 in words is "eleven million, one hundred twenty-one thousand, eight hundred twenty-one".