19881224 has 32 divisors (see below), whose sum is σ = 40953600. Its totient is φ = 8973120.

The previous prime is 19881193. The next prime is 19881227. The reversal of 19881224 is 42218891.

It is not an unprimeable number, because it can be changed into a prime (19881227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13097 + ... + 14535.

It is an arithmetic number, because the mean of its divisors is an integer number (1279800).

Almost surely, 2^19881224 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 19881224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20476800).

19881224 is an abundant number, since it is smaller than the sum of its proper divisors (21072376).

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

19881224 is a wasteful number, since it uses less digits than its factorization.

19881224 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1613 (or 1609 counting only the distinct ones).

The product of its digits is 9216, while the sum is 35.

The square root of 19881224 is about 4458.8366195679. The cubic root of 19881224 is about 270.9033482942.

The spelling of 19881224 in words is "nineteen million, eight hundred eighty-one thousand, two hundred twenty-four".