19892994688 has 64 divisors (see below), whose sum is σ = 45542689920. Its totient is φ = 8478397440.

The previous prime is 19892994647. The next prime is 19892994701. The reversal of 19892994688 is 88649929891.

It is a tau number, because it is divible by the number of its divisors (64).

It is a self number, because there is not a number n which added to its sum of digits gives 19892994688.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 100845 + ... + 223507.

It is an arithmetic number, because the mean of its divisors is an integer number (711604530).

Almost surely, 2^19892994688 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 19892994688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22771344960).

19892994688 is an abundant number, since it is smaller than the sum of its proper divisors (25649695232).

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

19892994688 is a wasteful number, since it uses less digits than its factorization.

19892994688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122865 (or 122853 counting only the distinct ones).

The product of its digits is 161243136, while the sum is 73.

The spelling of 19892994688 in words is "nineteen billion, eight hundred ninety-two million, nine hundred ninety-four thousand, six hundred eighty-eight".