128778158 has 4 divisors (see below), whose sum is σ = 193167240. Its totient is φ = 64389078.

The previous prime is 128778157. The next prime is 128778161. The reversal of 128778158 is 851877821.

It is a semiprime because it is the product of two primes.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128778157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32194538 + ... + 32194541.

It is an arithmetic number, because the mean of its divisors is an integer number (48291810).

Almost surely, 2^128778158 is an apocalyptic number.

128778158 is a deficient number, since it is larger than the sum of its proper divisors (64389082).

128778158 is an equidigital number, since it uses as much as digits as its factorization.

128778158 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64389081.

The product of its digits is 250880, while the sum is 47.

The square root of 128778158 is about 11348.0464398063. The cubic root of 128778158 is about 504.9876257465.

The spelling of 128778158 in words is "one hundred twenty-eight million, seven hundred seventy-eight thousand, one hundred fifty-eight".