19894374168 has 64 divisors (see below), whose sum is σ = 52805468160. Its totient is φ = 6224318976.

The previous prime is 19894374133. The next prime is 19894374173. The reversal of 19894374168 is 86147349891.

It is a super-2 number, since 2×19894374168² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83305 + ... + 216167.

It is an arithmetic number, because the mean of its divisors is an integer number (825085440).

Almost surely, 2^19894374168 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19894374168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26402734080).

19894374168 is an abundant number, since it is smaller than the sum of its proper divisors (32911093992).

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

19894374168 is a wasteful number, since it uses less digits than its factorization.

19894374168 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133256 (or 133252 counting only the distinct ones).

The product of its digits is 10450944, while the sum is 60.

The spelling of 19894374168 in words is "nineteen billion, eight hundred ninety-four million, three hundred seventy-four thousand, one hundred sixty-eight".