21748044569 has 2 divisors, whose sum is σ = 21748044570. Its totient is φ = 21748044568.

The previous prime is 21748044557. The next prime is 21748044599. The reversal of 21748044569 is 96544084712.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21263472400 + 484572169 = 145820^2 + 22013^2 .

It is a cyclic number.

It is not a de Polignac number, because 21748044569 - 2⁴ = 21748044553 is a prime.

It is a super-2 number, since 2×21748044569² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21748044509) 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, 10874022284 + 10874022285.

It is an arithmetic number, because the mean of its divisors is an integer number (10874022285).

Almost surely, 2^21748044569 is an apocalyptic number.

It is an amenable number.

21748044569 is a deficient number, since it is larger than the sum of its proper divisors (1).

21748044569 is an equidigital number, since it uses as much as digits as its factorization.

21748044569 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1935360, while the sum is 50.

The spelling of 21748044569 in words is "twenty-one billion, seven hundred forty-eight million, forty-four thousand, five hundred sixty-nine".