19819128689424 has 105 divisors (see below), whose sum is σ = 57574402330629. Its totient is φ = 6606215962560.

The previous prime is 19819128689411. The next prime is 19819128689431. The reversal of 19819128689424 is 42498682191891.

The square root of 19819128689424 is 4451868.

It is a perfect power (a square), and thus also a powerful number.

19819128689424 is a `hidden beast` number, since 1 + 9 + 8 + 19 + 128 + 68 + 9 + 424 = 666.

It can be written as a sum of positive squares in only one way, i.e., 3206004843024 + 16613123846400 = 1790532^2 + 4075920^2 .

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 20 ways as a sum of consecutive naturals, for example, 480781134 + ... + 480822354.

Almost surely, 2^{19819128689424} is an apocalyptic number.

19819128689424 is the 4451868-th square number.

It is an amenable number.

19819128689424 is an abundant number, since it is smaller than the sum of its proper divisors (37755273641205).

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

19819128689424 is an frugal number, since it uses more digits than its factorization.

19819128689424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82468 (or 41226 counting only the distinct ones).

The product of its digits is 143327232, while the sum is 72.

The spelling of 19819128689424 in words is "nineteen trillion, eight hundred nineteen billion, one hundred twenty-eight million, six hundred eighty-nine thousand, four hundred twenty-four".