21226540452517 has 2 divisors, whose sum is σ = 21226540452518. Its totient is φ = 21226540452516.

The previous prime is 21226540452449. The next prime is 21226540452553. The reversal of 21226540452517 is 71525404562212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14141819034721 + 7084721417796 = 3760561^2 + 2661714^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21226540452517 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21226540452587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10613270226258 + 10613270226259.

It is an arithmetic number, because the mean of its divisors is an integer number (10613270226259).

Almost surely, 2^{21226540452517} is an apocalyptic number.

It is an amenable number.

21226540452517 is a deficient number, since it is larger than the sum of its proper divisors (1).

21226540452517 is an equidigital number, since it uses as much as digits as its factorization.

21226540452517 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344000, while the sum is 46.

The spelling of 21226540452517 in words is "twenty-one trillion, two hundred twenty-six billion, five hundred forty million, four hundred fifty-two thousand, five hundred seventeen".