19989579850 has 96 divisors (see below), whose sum is σ = 40265280000. Its totient is φ = 7358662080.

The previous prime is 19989579847. The next prime is 19989579877. The reversal of 19989579850 is 5897598991.

It is a self number, because there is not a number n which added to its sum of digits gives 19989579850.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8127921 + ... + 8130379.

It is an arithmetic number, because the mean of its divisors is an integer number (419430000).

Almost surely, 2^19989579850 is an apocalyptic number.

19989579850 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19989579850 is an abundant number, since it is smaller than the sum of its proper divisors (20275700150).

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

19989579850 is a wasteful number, since it uses less digits than its factorization.

19989579850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2732 (or 2727 counting only the distinct ones).

The product of its (nonzero) digits is 73483200, while the sum is 70.

The spelling of 19989579850 in words is "nineteen billion, nine hundred eighty-nine million, five hundred seventy-nine thousand, eight hundred fifty".