11021921 has 4 divisors (see below), whose sum is σ = 11030292. Its totient is φ = 11013552.

The previous prime is 11021917. The next prime is 11021929. The reversal of 11021921 is 12912011.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 6071296 + 4950625 = 2464^2 + 2225^2 .

It is a cyclic number.

It is not a de Polignac number, because 11021921 - 2² = 11021917 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 11021921.

It is not an unprimeable number, because it can be changed into a prime (11021929) 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, 1730 + ... + 5003.

It is an arithmetic number, because the mean of its divisors is an integer number (2757573).

Almost surely, 2^11021921 is an apocalyptic number.

It is an amenable number.

11021921 is a deficient number, since it is larger than the sum of its proper divisors (8371).

11021921 is an equidigital number, since it uses as much as digits as its factorization.

11021921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8370.

The product of its (nonzero) digits is 36, while the sum is 17.

The square root of 11021921 is about 3319.9278606620. The cubic root of 11021921 is about 222.5456439625.

Adding to 11021921 its reverse (12912011), we get a palindrome (23933932).

The spelling of 11021921 in words is "eleven million, twenty-one thousand, nine hundred twenty-one".