19915778880 has 224 divisors, whose sum is σ = 72525818880. Its totient is φ = 5139486720.

The previous prime is 19915778879. The next prime is 19915778923. The reversal of 19915778880 is 8887751991.

It is a congruent number.

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 31 ways as a sum of consecutive naturals, for example, 230662 + ... + 305018.

Almost surely, 2^19915778880 is an apocalyptic number.

19915778880 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 19915778880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36262909440).

19915778880 is an abundant number, since it is smaller than the sum of its proper divisors (52610040000).

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

19915778880 is a wasteful number, since it uses less digits than its factorization.

19915778880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74414 (or 74398 counting only the distinct ones).

The product of its (nonzero) digits is 10160640, while the sum is 63.

The spelling of 19915778880 in words is "nineteen billion, nine hundred fifteen million, seven hundred seventy-eight thousand, eight hundred eighty".