19985945280 has 672 divisors, whose sum is σ = 79230638592. Its totient is φ = 4177920000.

The previous prime is 19985945257. The next prime is 19985945299. The reversal of 19985945280 is 8254958991.

It is a tau number, because it is divible by the number of its divisors (672).

It is a Harshad number since it is a multiple of its sum of digits (60).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 79625155 + ... + 79625405.

It is an arithmetic number, because the mean of its divisors is an integer number (117902736).

Almost surely, 2^19985945280 is an apocalyptic number.

19985945280 is a gapful number since it is divisible by the number (10) 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 19985945280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39615319296).

19985945280 is an abundant number, since it is smaller than the sum of its proper divisors (59244693312).

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

19985945280 is a wasteful number, since it uses less digits than its factorization.

19985945280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 353 (or 326 counting only the distinct ones).

The product of its (nonzero) digits is 9331200, while the sum is 60.

The spelling of 19985945280 in words is "nineteen billion, nine hundred eighty-five million, nine hundred forty-five thousand, two hundred eighty".