128983891 has 2 divisors, whose sum is σ = 128983892. Its totient is φ = 128983890.

The previous prime is 128983889. The next prime is 128983949. The reversal of 128983891 is 198389821.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 128983891 - 2¹ = 128983889 is a prime.

Together with 128983889, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (128983801) 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, 64491945 + 64491946.

It is an arithmetic number, because the mean of its divisors is an integer number (64491946).

Almost surely, 2^128983891 is an apocalyptic number.

128983891 is a deficient number, since it is larger than the sum of its proper divisors (1).

128983891 is an equidigital number, since it uses as much as digits as its factorization.

128983891 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 248832, while the sum is 49.

The square root of 128983891 is about 11357.1075102774. The cubic root of 128983891 is about 505.2564015089.

The spelling of 128983891 in words is "one hundred twenty-eight million, nine hundred eighty-three thousand, eight hundred ninety-one".