18844280 has 128 divisors (see below), whose sum is σ = 54190080. Its totient is φ = 5736960.

The previous prime is 18844207. The next prime is 18844283. The reversal of 18844280 is 8244881.

It is a Cunningham number, because it is equal to 4341²-1.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 18844280.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18844283) 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 31 ways as a sum of consecutive naturals, for example, 112757 + ... + 112923.

It is an arithmetic number, because the mean of its divisors is an integer number (423360).

Almost surely, 2^18844280 is an apocalyptic number.

18844280 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 18844280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27095040).

18844280 is an abundant number, since it is smaller than the sum of its proper divisors (35345800).

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

18844280 is a wasteful number, since it uses less digits than its factorization.

18844280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229 (or 225 counting only the distinct ones).

The product of its (nonzero) digits is 16384, while the sum is 35.

The square root of 18844280 is about 4340.9998848192. Note that the first 3 decimals coincide. The cubic root of 18844280 is about 266.1091756039.

The spelling of 18844280 in words is "eighteen million, eight hundred forty-four thousand, two hundred eighty".