11842821 has 8 divisors (see below), whose sum is σ = 17544960. Its totient is φ = 7895196.

The previous prime is 11842813. The next prime is 11842841. The reversal of 11842821 is 12824811.

It is not a de Polignac number, because 11842821 - 2³ = 11842813 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 438623 = 11842821 / (1 + 1 + 8 + 4 + 2 + 8 + 2 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11842801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 219285 + ... + 219338.

It is an arithmetic number, because the mean of its divisors is an integer number (2193120).

Almost surely, 2^11842821 is an apocalyptic number.

It is an amenable number.

11842821 is a deficient number, since it is larger than the sum of its proper divisors (5702139).

11842821 is an equidigital number, since it uses as much as digits as its factorization.

11842821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438632 (or 438626 counting only the distinct ones).

The product of its digits is 1024, while the sum is 27.

The square root of 11842821 is about 3441.3400006393. The cubic root of 11842821 is about 227.9388686525.

It can be divided in two parts, 1184 and 2821, that added together give a triangular number (4005 = T₈₉).

The spelling of 11842821 in words is "eleven million, eight hundred forty-two thousand, eight hundred twenty-one".