1644445141 has 2 divisors, whose sum is σ = 1644445142. Its totient is φ = 1644445140.

The previous prime is 1644445111. The next prime is 1644445247. The reversal of 1644445141 is 1415444461.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1636202500 + 8242641 = 40450^2 + 2871^2 .

It is a cyclic number.

It is not a de Polignac number, because 1644445141 - 2⁷ = 1644445013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1644445097 and 1644445106.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1644445111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822222570 + 822222571.

It is an arithmetic number, because the mean of its divisors is an integer number (822222571).

Almost surely, 2^1644445141 is an apocalyptic number.

It is an amenable number.

1644445141 is a deficient number, since it is larger than the sum of its proper divisors (1).

1644445141 is an equidigital number, since it uses as much as digits as its factorization.

1644445141 is an evil number, because the sum of its binary digits is even.

The product of its digits is 30720, while the sum is 34.

The square root of 1644445141 is about 40551.7587904643. The cubic root of 1644445141 is about 1180.3382016793.

The spelling of 1644445141 in words is "one billion, six hundred forty-four million, four hundred forty-five thousand, one hundred forty-one".