19987320 has 32 divisors (see below), whose sum is σ = 59962320. Its totient is φ = 5329920.

The previous prime is 19987309. The next prime is 19987333. The reversal of 19987320 is 2378991.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 83161 + ... + 83400.

Almost surely, 2^19987320 is an apocalyptic number.

19987320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19987320 is an abundant number, since it is smaller than the sum of its proper divisors (39975000).

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

19987320 is a wasteful number, since it uses less digits than its factorization.

19987320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166575 (or 166571 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 39.

The square root of 19987320 is about 4470.7180631304. The cubic root of 19987320 is about 271.3843848398.

The spelling of 19987320 in words is "nineteen million, nine hundred eighty-seven thousand, three hundred twenty".