128277889 has 4 divisors (see below), whose sum is σ = 131406660. Its totient is φ = 125149120.

The previous prime is 128277887. The next prime is 128277959. The reversal of 128277889 is 988772821.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 988772821 = 10831 ⋅91291.

It can be written as a sum of positive squares in 2 ways, for example, as 49210225 + 79067664 = 7015^2 + 8892^2 .

It is a cyclic number.

It is not a de Polignac number, because 128277889 - 2¹ = 128277887 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128277881) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1564324 + ... + 1564405.

It is an arithmetic number, because the mean of its divisors is an integer number (32851665).

Almost surely, 2^128277889 is an apocalyptic number.

It is an amenable number.

128277889 is a deficient number, since it is larger than the sum of its proper divisors (3128771).

128277889 is an equidigital number, since it uses as much as digits as its factorization.

128277889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3128770.

The product of its digits is 903168, while the sum is 52.

The square root of 128277889 is about 11325.9829154030. The cubic root of 128277889 is about 504.3328628080.

The spelling of 128277889 in words is "one hundred twenty-eight million, two hundred seventy-seven thousand, eight hundred eighty-nine".