128878 has 4 divisors (see below), whose sum is σ = 193320. Its totient is φ = 64438.
The previous prime is 128873. The next prime is 128879. The reversal of 128878 is 878821.
It is a semiprime because it is the product of two primes.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (128873) 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, 32218 + ... + 32221.
It is an arithmetic number, because the mean of its divisors is an integer number (48330).
2128878 is an apocalyptic number.
128878 is a deficient number, since it is larger than the sum of its proper divisors (64442).
128878 is an equidigital number, since it uses as much as digits as its factorization.
128878 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 64441.
The product of its digits is 7168, while the sum is 34.
The square root of 128878 is about 358.9958217027. The cubic root of 128878 is about 50.5118098054.
The spelling of 128878 in words is "one hundred twenty-eight thousand, eight hundred seventy-eight".
• e-mail: info -at- numbersaplenty.com • Privacy notice • done in 0.065 sec. • engine limits •