66131161 has 2 divisors, whose sum is σ = 66131162. Its totient is φ = 66131160.

The previous prime is 66131129. The next prime is 66131171. The reversal of 66131161 is 16113166.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49970761 + 16160400 = 7069^2 + 4020^2 .

It is a cyclic number.

It is not a de Polignac number, because 66131161 - 2⁵ = 66131129 is a prime.

It is not a weakly prime, because it can be changed into another prime (66131111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33065580 + 33065581.

It is an arithmetic number, because the mean of its divisors is an integer number (33065581).

Almost surely, 2^66131161 is an apocalyptic number.

It is an amenable number.

66131161 is a deficient number, since it is larger than the sum of its proper divisors (1).

66131161 is an equidigital number, since it uses as much as digits as its factorization.

66131161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 648, while the sum is 25.

The square root of 66131161 is about 8132.1067995938. The cubic root of 66131161 is about 404.3915285000.

The spelling of 66131161 in words is "sixty-six million, one hundred thirty-one thousand, one hundred sixty-one".