181888081 has 2 divisors, whose sum is σ = 181888082. Its totient is φ = 181888080.

The previous prime is 181888061. The next prime is 181888093. The reversal of 181888081 is 180888181.

181888081 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 148352400 + 33535681 = 12180^2 + 5791^2 .

It is a cyclic number.

It is not a de Polignac number, because 181888081 - 2¹⁵ = 181855313 is a prime.

It is a super-2 number, since 2×181888081² = 66166548019725122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (181888001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90944040 + 90944041.

It is an arithmetic number, because the mean of its divisors is an integer number (90944041).

Almost surely, 2^181888081 is an apocalyptic number.

It is an amenable number.

181888081 is a deficient number, since it is larger than the sum of its proper divisors (1).

181888081 is an equidigital number, since it uses as much as digits as its factorization.

181888081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32768, while the sum is 43.

The square root of 181888081 is about 13486.5889312309. The cubic root of 181888081 is about 566.5889238599.

The spelling of 181888081 in words is "one hundred eighty-one million, eight hundred eighty-eight thousand, eighty-one".