2004122221 has 4 divisors (see below), whose sum is σ = 2004230844. Its totient is φ = 2004013600.

The previous prime is 2004122213. The next prime is 2004122251. The reversal of 2004122221 is 1222214002.

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 1260960100 + 743162121 = 35510^2 + 27261^2 .

It is a cyclic number.

It is not a de Polignac number, because 2004122221 - 2³ = 2004122213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2004122195 and 2004122204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2004122251) 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, 18970 + ... + 66091.

It is an arithmetic number, because the mean of its divisors is an integer number (501057711).

Almost surely, 2^2004122221 is an apocalyptic number.

It is an amenable number.

2004122221 is a deficient number, since it is larger than the sum of its proper divisors (108623).

2004122221 is an equidigital number, since it uses as much as digits as its factorization.

2004122221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108622.

The product of its (nonzero) digits is 128, while the sum is 16.

The square root of 2004122221 is about 44767.4236582808. The cubic root of 2004122221 is about 1260.7860680358.

Adding to 2004122221 its reverse (1222214002), we get a palindrome (3226336223).

The spelling of 2004122221 in words is "two billion, four million, one hundred twenty-two thousand, two hundred twenty-one".