11000821 has 4 divisors (see below), whose sum is σ = 11847052. Its totient is φ = 10154592.

The previous prime is 11000809. The next prime is 11000827. The reversal of 11000821 is 12800011.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1322500 + 9678321 = 1150^2 + 3111^2 .

It is a cyclic number.

It is not a de Polignac number, because 11000821 - 2⁵ = 11000789 is a prime.

It is a super-5 number, since 5×11000821⁵ (a number of 36 digits) contains 55555 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 846217 = 11000821 / (1 + 1 + 0 + 0 + 0 + 8 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11000827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 423096 + ... + 423121.

It is an arithmetic number, because the mean of its divisors is an integer number (2961763).

Almost surely, 2^11000821 is an apocalyptic number.

It is an amenable number.

11000821 is a deficient number, since it is larger than the sum of its proper divisors (846231).

11000821 is an equidigital number, since it uses as much as digits as its factorization.

11000821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 846230.

The product of its (nonzero) digits is 16, while the sum is 13.

The square root of 11000821 is about 3316.7485584530. The cubic root of 11000821 is about 222.4035419122.

Adding to 11000821 its reverse (12800011), we get a palindrome (23800832).

The spelling of 11000821 in words is "eleven million, eight hundred twenty-one", and thus it is an aban number.