21744644231273 has 2 divisors, whose sum is σ = 21744644231274. Its totient is φ = 21744644231272.

The previous prime is 21744644231263. The next prime is 21744644231281. The reversal of 21744644231273 is 37213244644712.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20310597265984 + 1434046965289 = 4506728^2 + 1197517^2 .

It is a cyclic number.

It is not a de Polignac number, because 21744644231273 - 2⁴ = 21744644231257 is a prime.

It is a super-2 number, since 2×21744644231273² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21744644231263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10872322115636 + 10872322115637.

It is an arithmetic number, because the mean of its divisors is an integer number (10872322115637).

Almost surely, 2^{21744644231273} is an apocalyptic number.

It is an amenable number.

21744644231273 is a deficient number, since it is larger than the sum of its proper divisors (1).

21744644231273 is an equidigital number, since it uses as much as digits as its factorization.

21744644231273 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5419008, while the sum is 50.

Adding to 21744644231273 its reverse (37213244644712), we get a palindrome (58957888875985).

The spelling of 21744644231273 in words is "twenty-one trillion, seven hundred forty-four billion, six hundred forty-four million, two hundred thirty-one thousand, two hundred seventy-three".