643874519 has 2 divisors, whose sum is σ = 643874520. Its totient is φ = 643874518.

The previous prime is 643874503. The next prime is 643874587. The reversal of 643874519 is 915478346.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 643874519 - 2⁴ = 643874503 is a prime.

It is a super-2 number, since 2×643874519² = 829148792434962722, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643874219) 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, 321937259 + 321937260.

It is an arithmetic number, because the mean of its divisors is an integer number (321937260).

Almost surely, 2^643874519 is an apocalyptic number.

643874519 is a deficient number, since it is larger than the sum of its proper divisors (1).

643874519 is an equidigital number, since it uses as much as digits as its factorization.

643874519 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 725760, while the sum is 47.

The square root of 643874519 is about 25374.6826384095. The cubic root of 643874519 is about 863.5094196995.

The spelling of 643874519 in words is "six hundred forty-three million, eight hundred seventy-four thousand, five hundred nineteen".