18318540 has 48 divisors (see below), whose sum is σ = 51780960. Its totient is φ = 4838400.

The previous prime is 18318539. The next prime is 18318541. The reversal of 18318540 is 4581381.

It is an interprime number because it is at equal distance from previous prime (18318539) and next prime (18318541).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 18318498 and 18318507.

It is not an unprimeable number, because it can be changed into a prime (18318541) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 5140 + ... + 7940.

It is an arithmetic number, because the mean of its divisors is an integer number (1078770).

Almost surely, 2^18318540 is an apocalyptic number.

18318540 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 18318540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25890480).

18318540 is an abundant number, since it is smaller than the sum of its proper divisors (33462420).

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

18318540 is a wasteful number, since it uses less digits than its factorization.

18318540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2922 (or 2920 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 30.

The square root of 18318540 is about 4280.0163551089. The cubic root of 18318540 is about 263.6110548976.

The spelling of 18318540 in words is "eighteen million, three hundred eighteen thousand, five hundred forty".