66168161 has 2 divisors, whose sum is σ = 66168162. Its totient is φ = 66168160.

The previous prime is 66168139. The next prime is 66168197. The reversal of 66168161 is 16186166.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65918161 + 250000 = 8119^2 + 500^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66168161 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (66168461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33084080 + 33084081.

It is an arithmetic number, because the mean of its divisors is an integer number (33084081).

Almost surely, 2^66168161 is an apocalyptic number.

It is an amenable number.

66168161 is a deficient number, since it is larger than the sum of its proper divisors (1).

66168161 is an equidigital number, since it uses as much as digits as its factorization.

66168161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10368, while the sum is 35.

The square root of 66168161 is about 8134.3814147113. The cubic root of 66168161 is about 404.4669326752.

The spelling of 66168161 in words is "sixty-six million, one hundred sixty-eight thousand, one hundred sixty-one".