18563944 has 96 divisors (see below), whose sum is σ = 44323200. Its totient is φ = 7244160.

The previous prime is 18563933. The next prime is 18563981. The reversal of 18563944 is 44936581.

It is a junction number, because it is equal to n+sod(n) for n = 18563897 and 18563906.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 261429 + ... + 261499.

It is an arithmetic number, because the mean of its divisors is an integer number (461700).

Almost surely, 2^18563944 is an apocalyptic number.

18563944 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 18563944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22161600).

18563944 is an abundant number, since it is smaller than the sum of its proper divisors (25759256).

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

18563944 is a wasteful number, since it uses less digits than its factorization.

18563944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143 (or 132 counting only the distinct ones).

The product of its digits is 103680, while the sum is 40.

The square root of 18563944 is about 4308.5895604014. The cubic root of 18563944 is about 264.7829907263.

The spelling of 18563944 in words is "eighteen million, five hundred sixty-three thousand, nine hundred forty-four".