11666600606509 has 2 divisors, whose sum is σ = 11666600606510. Its totient is φ = 11666600606508.

The previous prime is 11666600606491. The next prime is 11666600606539. The reversal of 11666600606509 is 90560600666611.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7833925177225 + 3832675429284 = 2798915^2 + 1957722^2 .

It is a cyclic number.

It is not a de Polignac number, because 11666600606509 - 2⁹ = 11666600605997 is a prime.

It is a super-2 number, since 2×11666600606509² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11666600606539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5833300303254 + 5833300303255.

It is an arithmetic number, because the mean of its divisors is an integer number (5833300303255).

Almost surely, 2^{11666600606509} is an apocalyptic number.

It is an amenable number.

11666600606509 is a deficient number, since it is larger than the sum of its proper divisors (1).

11666600606509 is an equidigital number, since it uses as much as digits as its factorization.

11666600606509 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2099520, while the sum is 52.

The spelling of 11666600606509 in words is "eleven trillion, six hundred sixty-six billion, six hundred million, six hundred six thousand, five hundred nine".