1644213113 has 2 divisors, whose sum is σ = 1644213114. Its totient is φ = 1644213112.

The previous prime is 1644213107. The next prime is 1644213139. The reversal of 1644213113 is 3113124461.

It is a happy number.

It is an a-pointer prime, because the next prime (1644213139) can be obtained adding 1644213113 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1534445584 + 109767529 = 39172^2 + 10477^2 .

It is an emirp because it is prime and its reverse (3113124461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1644213113 - 2⁶ = 1644213049 is a prime.

It is a super-3 number, since 3×1644213113³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1644213413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822106556 + 822106557.

It is an arithmetic number, because the mean of its divisors is an integer number (822106557).

Almost surely, 2^1644213113 is an apocalyptic number.

It is an amenable number.

1644213113 is a deficient number, since it is larger than the sum of its proper divisors (1).

1644213113 is an equidigital number, since it uses as much as digits as its factorization.

1644213113 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1728, while the sum is 26.

The square root of 1644213113 is about 40548.8978025297. The cubic root of 1644213113 is about 1180.2826845959.

Adding to 1644213113 its reverse (3113124461), we get a palindrome (4757337574).

The spelling of 1644213113 in words is "one billion, six hundred forty-four million, two hundred thirteen thousand, one hundred thirteen".