181011161 has 2 divisors, whose sum is σ = 181011162. Its totient is φ = 181011160.

The previous prime is 181011101. The next prime is 181011167. The reversal of 181011161 is 161110181.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 179051161 + 1960000 = 13381^2 + 1400^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-181011161 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (181011167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90505580 + 90505581.

It is an arithmetic number, because the mean of its divisors is an integer number (90505581).

Almost surely, 2^181011161 is an apocalyptic number.

It is an amenable number.

181011161 is a deficient number, since it is larger than the sum of its proper divisors (1).

181011161 is an equidigital number, since it uses as much as digits as its factorization.

181011161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 20.

The square root of 181011161 is about 13454.0388359778. The cubic root of 181011161 is about 565.6769092130.

The spelling of 181011161 in words is "one hundred eighty-one million, eleven thousand, one hundred sixty-one".