19992191718 has 16 divisors (see below), whose sum is σ = 39993420096. Its totient is φ = 6662557800.

The previous prime is 19992191711. The next prime is 19992191719. The reversal of 19992191718 is 81719129991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19992191711) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 347596 + ... + 401007.

It is an arithmetic number, because the mean of its divisors is an integer number (2499588756).

Almost surely, 2^19992191718 is an apocalyptic number.

19992191718 is an abundant number, since it is smaller than the sum of its proper divisors (20001228378).

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

19992191718 is a wasteful number, since it uses less digits than its factorization.

19992191718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 753059.

The product of its digits is 734832, while the sum is 57.

The spelling of 19992191718 in words is "nineteen billion, nine hundred ninety-two million, one hundred ninety-one thousand, seven hundred eighteen".