2021821818404 has 12 divisors (see below), whose sum is σ = 3564014374284. Its totient is φ = 1003531997184.

The previous prime is 2021821818403. The next prime is 2021821818421. The reversal of 2021821818404 is 4048181281202.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 915542785600 + 1106279032804 = 956840^2 + 1051798^2 .

It is not an unprimeable number, because it can be changed into a prime (2021821818403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1844727389 + ... + 1844728484.

It is an arithmetic number, because the mean of its divisors is an integer number (297001197857).

Almost surely, 2^{2021821818404} is an apocalyptic number.

It is an amenable number.

2021821818404 is a deficient number, since it is larger than the sum of its proper divisors (1542192555880).

2021821818404 is a wasteful number, since it uses less digits than its factorization.

2021821818404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3689456014 (or 3689456012 counting only the distinct ones).

The product of its (nonzero) digits is 65536, while the sum is 41.

The spelling of 2021821818404 in words is "two trillion, twenty-one billion, eight hundred twenty-one million, eight hundred eighteen thousand, four hundred four".