4917172566521 has 2 divisors, whose sum is σ = 4917172566522. Its totient is φ = 4917172566520.

The previous prime is 4917172566499. The next prime is 4917172566571. The reversal of 4917172566521 is 1256652717194.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2696610642496 + 2220561924025 = 1642136^2 + 1490155^2 .

It is a cyclic number.

It is not a de Polignac number, because 4917172566521 - 2¹⁴ = 4917172550137 is a prime.

It is not a weakly prime, because it can be changed into another prime (4917172566571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2458586283260 + 2458586283261.

It is an arithmetic number, because the mean of its divisors is an integer number (2458586283261).

Almost surely, 2^{4917172566521} is an apocalyptic number.

It is an amenable number.

4917172566521 is a deficient number, since it is larger than the sum of its proper divisors (1).

4917172566521 is an equidigital number, since it uses as much as digits as its factorization.

4917172566521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6350400, while the sum is 56.

The spelling of 4917172566521 in words is "four trillion, nine hundred seventeen billion, one hundred seventy-two million, five hundred sixty-six thousand, five hundred twenty-one".