1919128878 has 96 divisors (see below), whose sum is σ = 4612847616. Its totient is φ = 573560064.

The previous prime is 1919128843. The next prime is 1919128927. The reversal of 1919128878 is 8788219191.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2582575 + ... + 2583317.

It is an arithmetic number, because the mean of its divisors is an integer number (48050496).

Almost surely, 2^1919128878 is an apocalyptic number.

1919128878 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1919128878, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2306423808).

1919128878 is an abundant number, since it is smaller than the sum of its proper divisors (2693718738).

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

1919128878 is a wasteful number, since it uses less digits than its factorization.

1919128878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1158 (or 1155 counting only the distinct ones).

The product of its digits is 580608, while the sum is 54.

The square root of 1919128878 is about 43807.8631982890. The cubic root of 1919128878 is about 1242.7050032106.

The spelling of 1919128878 in words is "one billion, nine hundred nineteen million, one hundred twenty-eight thousand, eight hundred seventy-eight".