19987968 has 240 divisors, whose sum is σ = 71888256. Its totient is φ = 4792320.

The previous prime is 19987949. The next prime is 19987969. The reversal of 19987968 is 86978991.

Its product of digits (1959552) is a multiple of the sum of its prime divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19987969) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1537530 + ... + 1537542.

Almost surely, 2^19987968 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19987968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35944128).

19987968 is an abundant number, since it is smaller than the sum of its proper divisors (51900288).

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

19987968 is a wasteful number, since it uses less digits than its factorization.

19987968 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65 (or 36 counting only the distinct ones).

The product of its digits is 1959552, while the sum is 57.

The square root of 19987968 is about 4470.7905341226. The cubic root of 19987968 is about 271.3873176189.

The spelling of 19987968 in words is "nineteen million, nine hundred eighty-seven thousand, nine hundred sixty-eight".