19887105420 has 504 divisors, whose sum is σ = 77556167136. Its totient is φ = 4192321536.

The previous prime is 19887105401. The next prime is 19887105437. The reversal of 19887105420 is 2450178891.

19887105420 is a `hidden beast` number, since 1 + 98 + 8 + 7 + 10 + 542 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 167 ways as a sum of consecutive naturals, for example, 17247564 + ... + 17248716.

It is an arithmetic number, because the mean of its divisors is an integer number (153881284).

Almost surely, 2^19887105420 is an apocalyptic number.

19887105420 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 19887105420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38778083568).

19887105420 is an abundant number, since it is smaller than the sum of its proper divisors (57669061716).

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

19887105420 is a wasteful number, since it uses less digits than its factorization.

19887105420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1213 (or 1183 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The spelling of 19887105420 in words is "nineteen billion, eight hundred eighty-seven million, one hundred five thousand, four hundred twenty".