166581185611 has 2 divisors, whose sum is σ = 166581185612. Its totient is φ = 166581185610.

The previous prime is 166581185587. The next prime is 166581185653. The reversal of 166581185611 is 116581185661.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 166581185611 - 2⁵ = 166581185579 is a prime.

It is not a weakly prime, because it can be changed into another prime (166581185411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83290592805 + 83290592806.

It is an arithmetic number, because the mean of its divisors is an integer number (83290592806).

Almost surely, 2^166581185611 is an apocalyptic number.

166581185611 is a deficient number, since it is larger than the sum of its proper divisors (1).

166581185611 is an equidigital number, since it uses as much as digits as its factorization.

166581185611 is an evil number, because the sum of its binary digits is even.

The product of its digits is 345600, while the sum is 49.

The spelling of 166581185611 in words is "one hundred sixty-six billion, five hundred eighty-one million, one hundred eighty-five thousand, six hundred eleven".