6643217101 has 2 divisors, whose sum is σ = 6643217102. Its totient is φ = 6643217100.

The previous prime is 6643217099. The next prime is 6643217123. The reversal of 6643217101 is 1017123466.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5952894025 + 690323076 = 77155^2 + 26274^2 .

It is a cyclic number.

It is not a de Polignac number, because 6643217101 - 2¹ = 6643217099 is a prime.

Together with 6643217099, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6643217401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3321608550 + 3321608551.

It is an arithmetic number, because the mean of its divisors is an integer number (3321608551).

Almost surely, 2^6643217101 is an apocalyptic number.

It is an amenable number.

6643217101 is a deficient number, since it is larger than the sum of its proper divisors (1).

6643217101 is an equidigital number, since it uses as much as digits as its factorization.

6643217101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6048, while the sum is 31.

The square root of 6643217101 is about 81505.9329190213. The cubic root of 6643217101 is about 1879.8627767844.

The spelling of 6643217101 in words is "six billion, six hundred forty-three million, two hundred seventeen thousand, one hundred one".