20811828 has 48 divisors (see below), whose sum is σ = 50694336. Its totient is φ = 6639360.

The previous prime is 20811827. The next prime is 20811853. The reversal of 20811828 is 82811802.

It is a junction number, because it is equal to n+sod(n) for n = 20811795 and 20811804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20811823) 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 15 ways as a sum of consecutive naturals, for example, 26968 + ... + 27728.

It is an arithmetic number, because the mean of its divisors is an integer number (1056132).

Almost surely, 2^20811828 is an apocalyptic number.

It is an amenable number.

20811828 is an abundant number, since it is smaller than the sum of its proper divisors (29882508).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20811828 is a wasteful number, since it uses less digits than its factorization.

20811828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 864 (or 862 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 30.

The square root of 20811828 is about 4561.9982463828. The cubic root of 20811828 is about 275.0658927501.

The spelling of 20811828 in words is "twenty million, eight hundred eleven thousand, eight hundred twenty-eight".