643165417 has 2 divisors, whose sum is σ = 643165418. Its totient is φ = 643165416.

The previous prime is 643165381. The next prime is 643165429. The reversal of 643165417 is 714561346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 352087696 + 291077721 = 18764^2 + 17061^2 .

It is a cyclic number.

It is not a de Polignac number, because 643165417 - 2²³ = 634776809 is a prime.

It is not a weakly prime, because it can be changed into another prime (643165217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321582708 + 321582709.

It is an arithmetic number, because the mean of its divisors is an integer number (321582709).

Almost surely, 2^643165417 is an apocalyptic number.

It is an amenable number.

643165417 is a deficient number, since it is larger than the sum of its proper divisors (1).

643165417 is an equidigital number, since it uses as much as digits as its factorization.

643165417 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 60480, while the sum is 37.

The square root of 643165417 is about 25360.7061613039. The cubic root of 643165417 is about 863.1923076130.

The spelling of 643165417 in words is "six hundred forty-three million, one hundred sixty-five thousand, four hundred seventeen".