643001000123 has 2 divisors, whose sum is σ = 643001000124. Its totient is φ = 643001000122.

The previous prime is 643001000107. The next prime is 643001000203. The reversal of 643001000123 is 321000100346.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 643001000123 - 2⁴ = 643001000107 is a prime.

It is a Sophie Germain prime.

It is a junction number, because it is equal to n+sod(n) for n = 643001000095 and 643001000104.

It is not a weakly prime, because it can be changed into another prime (643001000623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321500500061 + 321500500062.

It is an arithmetic number, because the mean of its divisors is an integer number (321500500062).

Almost surely, 2^643001000123 is an apocalyptic number.

643001000123 is a deficient number, since it is larger than the sum of its proper divisors (1).

643001000123 is an equidigital number, since it uses as much as digits as its factorization.

643001000123 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 643001000123 its reverse (321000100346), we get a palindrome (964001100469).

The spelling of 643001000123 in words is "six hundred forty-three billion, one million, one hundred twenty-three", and thus it is an aban number.