9640666109 has 2 divisors, whose sum is σ = 9640666110. Its totient is φ = 9640666108.

The previous prime is 9640666103. The next prime is 9640666111. The reversal of 9640666109 is 9016660469.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9458146009 + 182520100 = 97253^2 + 13510^2 .

It is a cyclic number.

It is not a de Polignac number, because 9640666109 - 2²⁴ = 9623888893 is a prime.

Together with 9640666111, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9640666103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4820333054 + 4820333055.

It is an arithmetic number, because the mean of its divisors is an integer number (4820333055).

Almost surely, 2^9640666109 is an apocalyptic number.

It is an amenable number.

9640666109 is a deficient number, since it is larger than the sum of its proper divisors (1).

9640666109 is an equidigital number, since it uses as much as digits as its factorization.

9640666109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 419904, while the sum is 47.

The square root of 9640666109 is about 98186.8937740674. The cubic root of 9640666109 is about 2128.3138962264.

The spelling of 9640666109 in words is "nine billion, six hundred forty million, six hundred sixty-six thousand, one hundred nine".