19776977128 has 16 divisors (see below), whose sum is σ = 37178657280. Its totient is φ = 9862668528.

The previous prime is 19776977123. The next prime is 19776977137. The reversal of 19776977128 is 82177967791.

It is a happy number.

It is a super-2 number, since 2×19776977128² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 19776977128.

It is not an unprimeable number, because it can be changed into a prime (19776977123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3224250 + ... + 3230377.

It is an arithmetic number, because the mean of its divisors is an integer number (2323666080).

Almost surely, 2^19776977128 is an apocalyptic number.

It is an amenable number.

19776977128 is a deficient number, since it is larger than the sum of its proper divisors (17401680152).

19776977128 is a wasteful number, since it uses less digits than its factorization.

19776977128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6455016 (or 6455012 counting only the distinct ones).

The product of its digits is 18670176, while the sum is 64.

The spelling of 19776977128 in words is "nineteen billion, seven hundred seventy-six million, nine hundred seventy-seven thousand, one hundred twenty-eight".