18644472 has 256 divisors, whose sum is σ = 69120000. Its totient is φ = 4510080.

The previous prime is 18644459. The next prime is 18644501. The reversal of 18644472 is 27444681.

18644472 is a `hidden beast` number, since 1 + 8 + 644 + 4 + 7 + 2 = 666.

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

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 315979 + ... + 316037.

It is an arithmetic number, because the mean of its divisors is an integer number (270000).

Almost surely, 2^18644472 is an apocalyptic number.

18644472 is a gapful number since it is divisible by the number (12) 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 18644472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34560000).

18644472 is an abundant number, since it is smaller than the sum of its proper divisors (50475528).

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

18644472 is a wasteful number, since it uses less digits than its factorization.

18644472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111 (or 101 counting only the distinct ones).

The product of its digits is 43008, while the sum is 36.

The square root of 18644472 is about 4317.9245014243. The cubic root of 18644472 is about 265.1653032964.

It can be divided in two parts, 1864 and 4472, that added together give a palindrome (6336).

The spelling of 18644472 in words is "eighteen million, six hundred forty-four thousand, four hundred seventy-two".