643874503 has 2 divisors, whose sum is σ = 643874504. Its totient is φ = 643874502.

The previous prime is 643874467. The next prime is 643874519. The reversal of 643874503 is 305478346.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 643874503 - 2⁹ = 643873991 is a prime.

It is a super-2 number, since 2×643874503² = 829148751226994018, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643874593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321937251 + 321937252.

It is an arithmetic number, because the mean of its divisors is an integer number (321937252).

Almost surely, 2^643874503 is an apocalyptic number.

643874503 is a deficient number, since it is larger than the sum of its proper divisors (1).

643874503 is an equidigital number, since it uses as much as digits as its factorization.

643874503 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 241920, while the sum is 40.

The square root of 643874503 is about 25374.6823231346. The cubic root of 643874503 is about 863.5094125469.

The spelling of 643874503 in words is "six hundred forty-three million, eight hundred seventy-four thousand, five hundred three".