188888881 has 2 divisors, whose sum is σ = 188888882. Its totient is φ = 188888880.

The previous prime is 188888867. The next prime is 188888923.

188888881 is nontrivially palindromic in base 10.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 137264656 + 51624225 = 11716^2 + 7185^2 .

It is a palprime.

It is a cyclic number.

It is not a de Polignac number, because 188888881 - 2⁷ = 188888753 is a prime.

It is a super-2 number, since 2×188888881² = 71358018730864322, which contains 22 as substring.

188888881 is a strobogrammatic number because it is the same when read upside-down.

It is not a weakly prime, because it can be changed into another prime (188888831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 94444440 + 94444441.

It is an arithmetic number, because the mean of its divisors is an integer number (94444441).

Almost surely, 2^188888881 is an apocalyptic number.

It is an amenable number.

188888881 is a deficient number, since it is larger than the sum of its proper divisors (1).

188888881 is an equidigital number, since it uses as much as digits as its factorization.

188888881 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2097152, while the sum is 58.

The square root of 188888881 is about 13743.6851317250. The cubic root of 188888881 is about 573.7668655877.

The spelling of 188888881 in words is "one hundred eighty-eight million, eight hundred eighty-eight thousand, eight hundred eighty-one".