128840025 has 24 divisors (see below), whose sum is σ = 225548064. Its totient is φ = 64672000.

The previous prime is 128840021. The next prime is 128840027. The reversal of 128840025 is 520048821.

It is not a de Polignac number, because 128840025 - 2² = 128840021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 128839974 and 128840001.

It is not an unprimeable number, because it can be changed into a prime (128840021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 49251 + ... + 51800.

It is an arithmetic number, because the mean of its divisors is an integer number (9397836).

Almost surely, 2^128840025 is an apocalyptic number.

128840025 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128840025 is a deficient number, since it is larger than the sum of its proper divisors (96708039).

128840025 is a wasteful number, since it uses less digits than its factorization.

128840025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101081 (or 101076 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 30.

The square root of 128840025 is about 11350.7720001769. The cubic root of 128840025 is about 505.0684807305.

Adding to 128840025 its reverse (520048821), we get a palindrome (648888846).

The spelling of 128840025 in words is "one hundred twenty-eight million, eight hundred forty thousand, twenty-five".