128181589 has 2 divisors, whose sum is σ = 128181590. Its totient is φ = 128181588.

The previous prime is 128181587. The next prime is 128181593. The reversal of 128181589 is 985181821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67076100 + 61105489 = 8190^2 + 7817^2 .

It is a cyclic number.

It is not a de Polignac number, because 128181589 - 2¹ = 128181587 is a prime.

Together with 128181587, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128181583) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64090794 + 64090795.

It is an arithmetic number, because the mean of its divisors is an integer number (64090795).

Almost surely, 2^128181589 is an apocalyptic number.

It is an amenable number.

128181589 is a deficient number, since it is larger than the sum of its proper divisors (1).

128181589 is an equidigital number, since it uses as much as digits as its factorization.

128181589 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46080, while the sum is 43.

The square root of 128181589 is about 11321.7308305753. The cubic root of 128181589 is about 504.2066279764.

The spelling of 128181589 in words is "one hundred twenty-eight million, one hundred eighty-one thousand, five hundred eighty-nine".