1644244117 has 16 divisors (see below), whose sum is σ = 1724425200. Its totient is φ = 1565724160.

The previous prime is 1644244111. The next prime is 1644244127. The reversal of 1644244117 is 7114424461.

It can be written as a sum of positive squares in 8 ways, for example, as 109641841 + 1534602276 = 10471^2 + 39174^2 .

It is a cyclic number.

It is not a de Polignac number, because 1644244117 - 2⁷ = 1644243989 is a prime.

It is a super-3 number, since 3×1644244117³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1644244111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1746867 + ... + 1747807.

It is an arithmetic number, because the mean of its divisors is an integer number (107776575).

Almost surely, 2^1644244117 is an apocalyptic number.

It is an amenable number.

1644244117 is a deficient number, since it is larger than the sum of its proper divisors (80181083).

1644244117 is an equidigital number, since it uses as much as digits as its factorization.

1644244117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1736.

The product of its digits is 21504, while the sum is 34.

The square root of 1644244117 is about 40549.2801045839. The cubic root of 1644244117 is about 1180.2901031911.

Adding to 1644244117 its reverse (7114424461), we get a palindrome (8758668578).

The spelling of 1644244117 in words is "one billion, six hundred forty-four million, two hundred forty-four thousand, one hundred seventeen".