18117432 has 80 divisors (see below), whose sum is σ = 51575040. Its totient is φ = 5940864.

The previous prime is 18117413. The next prime is 18117443. The reversal of 18117432 is 23471181.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 18117396 and 18117405.

It is a congruent number.

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 19 ways as a sum of consecutive naturals, for example, 47113 + ... + 47495.

It is an arithmetic number, because the mean of its divisors is an integer number (644688).

Almost surely, 2^18117432 is an apocalyptic number.

18117432 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 18117432, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25787520).

18117432 is an abundant number, since it is smaller than the sum of its proper divisors (33457608).

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

18117432 is a wasteful number, since it uses less digits than its factorization.

18117432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 474 (or 461 counting only the distinct ones).

The product of its digits is 1344, while the sum is 27.

The square root of 18117432 is about 4256.4576821578. The cubic root of 18117432 is about 262.6428283943.

The spelling of 18117432 in words is "eighteen million, one hundred seventeen thousand, four hundred thirty-two".