19868816 has 40 divisors (see below), whose sum is σ = 42556800. Its totient is φ = 8910720.

The previous prime is 19868791. The next prime is 19868819. The reversal of 19868816 is 61886891.

It is not an unprimeable number, because it can be changed into a prime (19868819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13190 + ... + 14618.

It is an arithmetic number, because the mean of its divisors is an integer number (1063920).

Almost surely, 2^19868816 is an apocalyptic number.

19868816 is a gapful number since it is divisible by the number (16) 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 19868816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21278400).

19868816 is an abundant number, since it is smaller than the sum of its proper divisors (22687984).

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

19868816 is a wasteful number, since it uses less digits than its factorization.

19868816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1527 (or 1521 counting only the distinct ones).

The product of its digits is 165888, while the sum is 47.

The square root of 19868816 is about 4457.4450080736. The cubic root of 19868816 is about 270.8469790574.

The spelling of 19868816 in words is "nineteen million, eight hundred sixty-eight thousand, eight hundred sixteen".