66149688694171 has 2 divisors, whose sum is σ = 66149688694172. Its totient is φ = 66149688694170.

The previous prime is 66149688694157. The next prime is 66149688694289. The reversal of 66149688694171 is 17149688694166.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66149688694171 - 2⁹ = 66149688693659 is a prime.

It is not a weakly prime, because it can be changed into another prime (66149688691171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33074844347085 + 33074844347086.

It is an arithmetic number, because the mean of its divisors is an integer number (33074844347086).

Almost surely, 2^{66149688694171} is an apocalyptic number.

66149688694171 is a deficient number, since it is larger than the sum of its proper divisors (1).

66149688694171 is an equidigital number, since it uses as much as digits as its factorization.

66149688694171 is an evil number, because the sum of its binary digits is even.

The product of its digits is 752467968, while the sum is 76.

The spelling of 66149688694171 in words is "sixty-six trillion, one hundred forty-nine billion, six hundred eighty-eight million, six hundred ninety-four thousand, one hundred seventy-one".