643536206101 has 2 divisors, whose sum is σ = 643536206102. Its totient is φ = 643536206100.

The previous prime is 643536206039. The next prime is 643536206129. The reversal of 643536206101 is 101602635346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 607462801201 + 36073404900 = 779399^2 + 189930^2 .

It is a cyclic number.

It is not a de Polignac number, because 643536206101 - 2⁷ = 643536205973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (643536216101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321768103050 + 321768103051.

It is an arithmetic number, because the mean of its divisors is an integer number (321768103051).

Almost surely, 2^643536206101 is an apocalyptic number.

It is an amenable number.

643536206101 is a deficient number, since it is larger than the sum of its proper divisors (1).

643536206101 is an equidigital number, since it uses as much as digits as its factorization.

643536206101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 77760, while the sum is 37.

The spelling of 643536206101 in words is "six hundred forty-three billion, five hundred thirty-six million, two hundred six thousand, one hundred one".