19821648 has 160 divisors (see below), whose sum is σ = 66281472. Its totient is φ = 4953600.

The previous prime is 19821647. The next prime is 19821649. The reversal of 19821648 is 84612891.

It is an interprime number because it is at equal distance from previous prime (19821647) and next prime (19821649).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19821647) 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 31 ways as a sum of consecutive naturals, for example, 114490 + ... + 114662.

Almost surely, 2^19821648 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 19821648, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33140736).

19821648 is an abundant number, since it is smaller than the sum of its proper divisors (46459824).

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

19821648 is a wasteful number, since it uses less digits than its factorization.

19821648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233 (or 227 counting only the distinct ones).

The product of its digits is 27648, while the sum is 39.

The square root of 19821648 is about 4452.1509408375. The cubic root of 19821648 is about 270.6324815743.

The spelling of 19821648 in words is "nineteen million, eight hundred twenty-one thousand, six hundred forty-eight".