18881744 has 60 divisors (see below), whose sum is σ = 44220384. Its totient is φ = 7649856.

The previous prime is 18881719. The next prime is 18881749. The reversal of 18881744 is 44718881.

Added to its reverse (44718881) it gives a square (63600625 = 7975²).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18881749) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40199 + ... + 40665.

Almost surely, 2^18881744 is an apocalyptic number.

18881744 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 18881744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22110192).

18881744 is an abundant number, since it is smaller than the sum of its proper divisors (25338640).

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

18881744 is a wasteful number, since it uses less digits than its factorization.

18881744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520 (or 495 counting only the distinct ones).

The product of its digits is 57344, while the sum is 41.

The square root of 18881744 is about 4345.3128771125. The cubic root of 18881744 is about 266.2854079443.

Adding to 18881744 its reverse (44718881), we get a square (63600625 = 7975²).

The spelling of 18881744 in words is "eighteen million, eight hundred eighty-one thousand, seven hundred forty-four".