4405644721 has 2 divisors, whose sum is σ = 4405644722. Its totient is φ = 4405644720.

The previous prime is 4405644671. The next prime is 4405644883. The reversal of 4405644721 is 1274465044.

4405644721 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4405640625 + 4096 = 66375^2 + 64^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-4405644721 is a prime.

It is not a weakly prime, because it can be changed into another prime (4405644521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2202822360 + 2202822361.

It is an arithmetic number, because the mean of its divisors is an integer number (2202822361).

Almost surely, 2^4405644721 is an apocalyptic number.

It is an amenable number.

4405644721 is a deficient number, since it is larger than the sum of its proper divisors (1).

4405644721 is an equidigital number, since it uses as much as digits as its factorization.

4405644721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 107520, while the sum is 37.

The square root of 4405644721 is about 66375.0308549834. The cubic root of 4405644721 is about 1639.3429750904.

The spelling of 4405644721 in words is "four billion, four hundred five million, six hundred forty-four thousand, seven hundred twenty-one".