643515074513 has 2 divisors, whose sum is σ = 643515074514. Its totient is φ = 643515074512.

The previous prime is 643515074497. The next prime is 643515074563. The reversal of 643515074513 is 315470515346.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 544574630209 + 98940444304 = 737953^2 + 314548^2 .

It is a cyclic number.

It is not a de Polignac number, because 643515074513 - 2⁴ = 643515074497 is a prime.

It is a super-2 number, since 2×643515074513² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (643515074563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321757537256 + 321757537257.

It is an arithmetic number, because the mean of its divisors is an integer number (321757537257).

Almost surely, 2^643515074513 is an apocalyptic number.

It is an amenable number.

643515074513 is a deficient number, since it is larger than the sum of its proper divisors (1).

643515074513 is an equidigital number, since it uses as much as digits as its factorization.

643515074513 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756000, while the sum is 44.

Adding to 643515074513 its reverse (315470515346), we get a palindrome (958985589859).

The spelling of 643515074513 in words is "six hundred forty-three billion, five hundred fifteen million, seventy-four thousand, five hundred thirteen".