128191513878 has 24 divisors (see below), whose sum is σ = 278113287816. Its totient is φ = 42674349600.

The previous prime is 128191513861. The next prime is 128191513927. The reversal of 128191513878 is 878315191821.

128191513878 is a `hidden beast` number, since 1 + 28 + 191 + 51 + 387 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4665508 + ... + 4692903.

It is an arithmetic number, because the mean of its divisors is an integer number (11588053659).

Almost surely, 2^128191513878 is an apocalyptic number.

128191513878 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

128191513878 is an abundant number, since it is smaller than the sum of its proper divisors (149921773938).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

128191513878 is a wasteful number, since it uses less digits than its factorization.

128191513878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9359180 (or 9359177 counting only the distinct ones).

The product of its digits is 967680, while the sum is 54.

The spelling of 128191513878 in words is "one hundred twenty-eight billion, one hundred ninety-one million, five hundred thirteen thousand, eight hundred seventy-eight".