19438920 has 128 divisors (see below), whose sum is σ = 66528000. Its totient is φ = 5045760.

The previous prime is 19438883. The next prime is 19438921. The reversal of 19438920 is 2983491.

It is a super-2 number, since 2×19438920² = 755743221532800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (19438921) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44061 + ... + 44499.

It is an arithmetic number, because the mean of its divisors is an integer number (519750).

Almost surely, 2^19438920 is an apocalyptic number.

19438920 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 19438920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33264000).

19438920 is an abundant number, since it is smaller than the sum of its proper divisors (47089080).

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

19438920 is a wasteful number, since it uses less digits than its factorization.

19438920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 500 (or 490 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 36.

The square root of 19438920 is about 4408.9590608215. The cubic root of 19438920 is about 268.8793053626.

The spelling of 19438920 in words is "nineteen million, four hundred thirty-eight thousand, nine hundred twenty".