19856144 has 80 divisors (see below), whose sum is σ = 48854016. Its totient is φ = 7593600.

The previous prime is 19856141. The next prime is 19856149. The reversal of 19856144 is 44165891.

It is a junction number, because it is equal to n+sod(n) for n = 19856098 and 19856107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19856141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87359 + ... + 87585.

Almost surely, 2^19856144 is an apocalyptic number.

19856144 is a gapful number since it is divisible by the number (14) 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 19856144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24427008).

19856144 is an abundant number, since it is smaller than the sum of its proper divisors (28997872).

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

19856144 is a wasteful number, since it uses less digits than its factorization.

19856144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324 (or 318 counting only the distinct ones).

The product of its digits is 34560, while the sum is 38.

The square root of 19856144 is about 4456.0233392567. The cubic root of 19856144 is about 270.7893862473.

The spelling of 19856144 in words is "nineteen million, eight hundred fifty-six thousand, one hundred forty-four".