646743101 has 2 divisors, whose sum is σ = 646743102. Its totient is φ = 646743100.

The previous prime is 646743079. The next prime is 646743133. The reversal of 646743101 is 101347646.

It is an a-pointer prime, because the next prime (646743133) can be obtained adding 646743101 to its sum of digits (32).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 333099001 + 313644100 = 18251^2 + 17710^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-646743101 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (646743151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 323371550 + 323371551.

It is an arithmetic number, because the mean of its divisors is an integer number (323371551).

Almost surely, 2^646743101 is an apocalyptic number.

It is an amenable number.

646743101 is a deficient number, since it is larger than the sum of its proper divisors (1).

646743101 is an equidigital number, since it uses as much as digits as its factorization.

646743101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12096, while the sum is 32.

The square root of 646743101 is about 25431.1443116506. The cubic root of 646743101 is about 864.7898855937.

The spelling of 646743101 in words is "six hundred forty-six million, seven hundred forty-three thousand, one hundred one".