128117878 has 16 divisors (see below), whose sum is σ = 220162464. Its totient is φ = 54774720.

The previous prime is 128117861. The next prime is 128117881. The reversal of 128117878 is 878711821.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4975 + ... + 16762.

It is an arithmetic number, because the mean of its divisors is an integer number (13760154).

Almost surely, 2^128117878 is an apocalyptic number.

128117878 is a deficient number, since it is larger than the sum of its proper divisors (92044586).

128117878 is a wasteful number, since it uses less digits than its factorization.

128117878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22167.

The product of its digits is 50176, while the sum is 43.

The square root of 128117878 is about 11318.9168209683. The cubic root of 128117878 is about 504.1230776725.

The spelling of 128117878 in words is "one hundred twenty-eight million, one hundred seventeen thousand, eight hundred seventy-eight".