866132653405909 has 2 divisors, whose sum is σ = 866132653405910. Its totient is φ = 866132653405908.

The previous prime is 866132653405871. The next prime is 866132653405939. The reversal of 866132653405909 is 909504356231668.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 616468068000625 + 249664585405284 = 24828775^2 + 15800778^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-866132653405909 is a prime.

It is a super-2 number, since 2×866132653405909² (a number of 31 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (866132653405939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 433066326702954 + 433066326702955.

It is an arithmetic number, because the mean of its divisors is an integer number (433066326702955).

Almost surely, 2^{866132653405909} is an apocalyptic number.

It is an amenable number.

866132653405909 is a deficient number, since it is larger than the sum of its proper divisors (1).

866132653405909 is an equidigital number, since it uses as much as digits as its factorization.

866132653405909 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 251942400, while the sum is 67.

The spelling of 866132653405909 in words is "eight hundred sixty-six trillion, one hundred thirty-two billion, six hundred fifty-three million, four hundred five thousand, nine hundred nine".