4004004440021 has 2 divisors, whose sum is σ = 4004004440022. Its totient is φ = 4004004440020.

The previous prime is 4004004440011. The next prime is 4004004440069. The reversal of 4004004440021 is 1200444004004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2487436819921 + 1516567620100 = 1577161^2 + 1231490^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4004004440021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (4004004440011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2002002220010 + 2002002220011.

It is an arithmetic number, because the mean of its divisors is an integer number (2002002220011).

Almost surely, 2^{4004004440021} is an apocalyptic number.

It is an amenable number.

4004004440021 is a deficient number, since it is larger than the sum of its proper divisors (1).

4004004440021 is an equidigital number, since it uses as much as digits as its factorization.

4004004440021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2048, while the sum is 23.

Adding to 4004004440021 its reverse (1200444004004), we get a palindrome (5204448444025).

The spelling of 4004004440021 in words is "four trillion, four billion, four million, four hundred forty thousand, twenty-one".