18918282240 has 1320 divisors, whose sum is σ = 83014774920. Its totient is φ = 4087480320.

The previous prime is 18918282191. The next prime is 18918282283. The reversal of 18918282240 is 4228281981.

It can be written as a sum of positive squares in 4 ways, for example, as 361304064 + 18556978176 = 19008^2 + 136224^2 .

It is a tau number, because it is divible by the number of its divisors (1320).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

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 119 ways as a sum of consecutive naturals, for example, 652354546 + ... + 652354574.

It is an arithmetic number, because the mean of its divisors is an integer number (62889981).

Almost surely, 2^18918282240 is an apocalyptic number.

18918282240 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 18918282240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41507387460).

18918282240 is an abundant number, since it is smaller than the sum of its proper divisors (64096492680).

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

18918282240 is a wasteful number, since it uses less digits than its factorization.

18918282240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101 (or 63 counting only the distinct ones).

The product of its (nonzero) digits is 147456, while the sum is 45.

The spelling of 18918282240 in words is "eighteen billion, nine hundred eighteen million, two hundred eighty-two thousand, two hundred forty".