19443920 has 90 divisors (see below), whose sum is σ = 49735842. Its totient is φ = 7067648.

The previous prime is 19443911. The next prime is 19443923. The reversal of 19443920 is 2934491.

It is a happy number.

It can be written as a sum of positive squares in 9 ways, for example, as 399424 + 19044496 = 632^2 + 4364^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19443923) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 670466 + ... + 670494.

Almost surely, 2^19443920 is an apocalyptic number.

19443920 is a gapful number since it is divisible by the number (10) 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 19443920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24867921).

19443920 is an abundant number, since it is smaller than the sum of its proper divisors (30291922).

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

19443920 is a wasteful number, since it uses less digits than its factorization.

19443920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105 (or 53 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 19443920 is about 4409.5260516296. The cubic root of 19443920 is about 268.9023567337.

The spelling of 19443920 in words is "nineteen million, four hundred forty-three thousand, nine hundred twenty".