440401021 has 4 divisors (see below), whose sum is σ = 440444412. Its totient is φ = 440357632.

The previous prime is 440401007. The next prime is 440401051. The reversal of 440401021 is 120104044.

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 364275396 + 76125625 = 19086^2 + 8725^2 .

It is a cyclic number.

It is not a de Polignac number, because 440401021 - 2¹³ = 440392829 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 440400986 and 440401004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (440401051) 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, 2595 + ... + 29791.

It is an arithmetic number, because the mean of its divisors is an integer number (110111103).

Almost surely, 2^440401021 is an apocalyptic number.

It is an amenable number.

440401021 is a deficient number, since it is larger than the sum of its proper divisors (43391).

440401021 is a wasteful number, since it uses less digits than its factorization.

440401021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43390.

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

The square root of 440401021 is about 20985.7337493832. The cubic root of 440401021 is about 760.8214922603.

Adding to 440401021 its reverse (120104044), we get a palindrome (560505065).

The spelling of 440401021 in words is "four hundred forty million, four hundred one thousand, twenty-one".