21750856001317 has 2 divisors, whose sum is σ = 21750856001318. Its totient is φ = 21750856001316.

The previous prime is 21750856001293. The next prime is 21750856001339. The reversal of 21750856001317 is 71310065805712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21594924997156 + 155931004161 = 4647034^2 + 394881^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21750856001317 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21750856071317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10875428000658 + 10875428000659.

It is an arithmetic number, because the mean of its divisors is an integer number (10875428000659).

Almost surely, 2^{21750856001317} is an apocalyptic number.

It is an amenable number.

21750856001317 is a deficient number, since it is larger than the sum of its proper divisors (1).

21750856001317 is an equidigital number, since it uses as much as digits as its factorization.

21750856001317 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 352800, while the sum is 46.

The spelling of 21750856001317 in words is "twenty-one trillion, seven hundred fifty billion, eight hundred fifty-six million, one thousand, three hundred seventeen".