444565621021 has 4 divisors (see below), whose sum is σ = 447810625692. Its totient is φ = 441320616352.

The previous prime is 444565621013. The next prime is 444565621067. The reversal of 444565621021 is 120126565444.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 329488628121 + 115076992900 = 574011^2 + 339230^2 .

It is a cyclic number.

It is not a de Polignac number, because 444565621021 - 2³ = 444565621013 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (444565621121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1622502130 + ... + 1622502403.

It is an arithmetic number, because the mean of its divisors is an integer number (111952656423).

Almost surely, 2^444565621021 is an apocalyptic number.

It is an amenable number.

444565621021 is a deficient number, since it is larger than the sum of its proper divisors (3245004671).

444565621021 is a wasteful number, since it uses less digits than its factorization.

444565621021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3245004670.

The product of its (nonzero) digits is 230400, while the sum is 40.

The spelling of 444565621021 in words is "four hundred forty-four billion, five hundred sixty-five million, six hundred twenty-one thousand, twenty-one".