444440021 has 2 divisors, whose sum is σ = 444440022. Its totient is φ = 444440020.

The previous prime is 444439951. The next prime is 444440047. The reversal of 444440021 is 120044444.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 434263921 + 10176100 = 20839^2 + 3190^2 .

It is a cyclic number.

It is not a de Polignac number, because 444440021 - 2¹⁰ = 444438997 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (444440071) 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, 222220010 + 222220011.

It is an arithmetic number, because the mean of its divisors is an integer number (222220011).

Almost surely, 2^444440021 is an apocalyptic number.

It is an amenable number.

444440021 is a deficient number, since it is larger than the sum of its proper divisors (1).

444440021 is an equidigital number, since it uses as much as digits as its factorization.

444440021 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.

The square root of 444440021 is about 21081.7461563315. The cubic root of 444440021 is about 763.1402965706.

Adding to 444440021 its reverse (120044444), we get a palindrome (564484465).

The spelling of 444440021 in words is "four hundred forty-four million, four hundred forty thousand, twenty-one".