66810943249 has 2 divisors, whose sum is σ = 66810943250. Its totient is φ = 66810943248.

The previous prime is 66810943201. The next prime is 66810943259. The reversal of 66810943249 is 94234901866.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35669988225 + 31140955024 = 188865^2 + 176468^2 .

It is a cyclic number.

It is not a de Polignac number, because 66810943249 - 2³⁵ = 32451204881 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66810943196 and 66810943205.

It is not a weakly prime, because it can be changed into another prime (66810943259) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33405471624 + 33405471625.

It is an arithmetic number, because the mean of its divisors is an integer number (33405471625).

Almost surely, 2^66810943249 is an apocalyptic number.

It is an amenable number.

66810943249 is a deficient number, since it is larger than the sum of its proper divisors (1).

66810943249 is an equidigital number, since it uses as much as digits as its factorization.

66810943249 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2239488, while the sum is 52.

The spelling of 66810943249 in words is "sixty-six billion, eight hundred ten million, nine hundred forty-three thousand, two hundred forty-nine".