643344011 has 2 divisors, whose sum is σ = 643344012. Its totient is φ = 643344010.

The previous prime is 643344001. The next prime is 643344019. The reversal of 643344011 is 110443346.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 643344011 - 2¹⁴ = 643327627 is a prime.

It is not a weakly prime, because it can be changed into another prime (643344019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321672005 + 321672006.

It is an arithmetic number, because the mean of its divisors is an integer number (321672006).

Almost surely, 2^643344011 is an apocalyptic number.

643344011 is a deficient number, since it is larger than the sum of its proper divisors (1).

643344011 is an equidigital number, since it uses as much as digits as its factorization.

643344011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 643344011 is about 25364.2269939377. The cubic root of 643344011 is about 863.2721972215.

Adding to 643344011 its reverse (110443346), we get a palindrome (753787357).

The spelling of 643344011 in words is "six hundred forty-three million, three hundred forty-four thousand, eleven".