440066021 has 2 divisors, whose sum is σ = 440066022. Its totient is φ = 440066020.

The previous prime is 440066009. The next prime is 440066071. The reversal of 440066021 is 120660044.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 374229025 + 65836996 = 19345^2 + 8114^2 .

It is a cyclic number.

It is not a de Polignac number, because 440066021 - 2²² = 435871717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (440066071) 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, 220033010 + 220033011.

It is an arithmetic number, because the mean of its divisors is an integer number (220033011).

Almost surely, 2^440066021 is an apocalyptic number.

It is an amenable number.

440066021 is a deficient number, since it is larger than the sum of its proper divisors (1).

440066021 is an equidigital number, since it uses as much as digits as its factorization.

440066021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 440066021 is about 20977.7506182145. The cubic root of 440066021 is about 760.6285318747.

The spelling of 440066021 in words is "four hundred forty million, sixty-six thousand, twenty-one".