66116655331 has 2 divisors, whose sum is σ = 66116655332. Its totient is φ = 66116655330.

The previous prime is 66116655313. The next prime is 66116655337. The reversal of 66116655331 is 13355661166.

Together with previous prime (66116655313) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66116655331 - 2⁵ = 66116655299 is a prime.

It is a super-2 number, since 2×66116655331² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66116655337) 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, 33058327665 + 33058327666.

It is an arithmetic number, because the mean of its divisors is an integer number (33058327666).

Almost surely, 2^66116655331 is an apocalyptic number.

66116655331 is a deficient number, since it is larger than the sum of its proper divisors (1).

66116655331 is an equidigital number, since it uses as much as digits as its factorization.

66116655331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 291600, while the sum is 43.

The spelling of 66116655331 in words is "sixty-six billion, one hundred sixteen million, six hundred fifty-five thousand, three hundred thirty-one".