19161658656 has 144 divisors (see below), whose sum is σ = 62537529600. Its totient is φ = 5451715584.

The previous prime is 19161658609. The next prime is 19161658673. The reversal of 19161658656 is 65685616191.

19161658656 is a `hidden beast` number, since 1 + 9 + 1 + 6 + 1 + 6 + 586 + 56 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 461940 + ... + 501708.

It is an arithmetic number, because the mean of its divisors is an integer number (434288400).

Almost surely, 2^19161658656 is an apocalyptic number.

19161658656 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19161658656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31268764800).

19161658656 is an abundant number, since it is smaller than the sum of its proper divisors (43375870944).

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

19161658656 is a wasteful number, since it uses less digits than its factorization.

19161658656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40031 (or 40020 counting only the distinct ones).

The product of its digits is 2332800, while the sum is 54.

The spelling of 19161658656 in words is "nineteen billion, one hundred sixty-one million, six hundred fifty-eight thousand, six hundred fifty-six".