19887920 has 60 divisors (see below), whose sum is σ = 50103936. Its totient is φ = 7338240.

The previous prime is 19887919. The next prime is 19887929. The reversal of 19887920 is 2978891.

It is not an unprimeable number, because it can be changed into a prime (19887929) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12785 + ... + 14255.

Almost surely, 2^19887920 is an apocalyptic number.

19887920 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 19887920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25051968).

19887920 is an abundant number, since it is smaller than the sum of its proper divisors (30216016).

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

19887920 is a wasteful number, since it uses less digits than its factorization.

19887920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1510 (or 1491 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 44.

The square root of 19887920 is about 4459.5874248634. The cubic root of 19887920 is about 270.9337583134.

The spelling of 19887920 in words is "nineteen million, eight hundred eighty-seven thousand, nine hundred twenty".