218241540 has 240 divisors, whose sum is σ = 769374144. Its totient is φ = 51321600.

The previous prime is 218241521. The next prime is 218241557. The reversal of 218241540 is 45142812.

218241540 is a `hidden beast` number, since 2 + 1 + 82 + 41 + 540 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 659175 + ... + 659505.

Almost surely, 2^218241540 is an apocalyptic number.

218241540 is a gapful number since it is divisible by the number (20) 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 218241540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (384687072).

218241540 is an abundant number, since it is smaller than the sum of its proper divisors (551132604).

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

218241540 is a wasteful number, since it uses less digits than its factorization.

218241540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400 (or 389 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 27.

The square root of 218241540 is about 14773.0003723008. Note that the first 3 decimals coincide. The cubic root of 218241540 is about 602.0683616072.

The spelling of 218241540 in words is "two hundred eighteen million, two hundred forty-one thousand, five hundred forty".