218400140 has 36 divisors (see below), whose sum is σ = 524580336. Its totient is φ = 74820096.

The previous prime is 218400137. The next prime is 218400181. The reversal of 218400140 is 41004812.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 174236 + ... + 175484.

It is an arithmetic number, because the mean of its divisors is an integer number (14571676).

Almost surely, 2^218400140 is an apocalyptic number.

218400140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

218400140 is an abundant number, since it is smaller than the sum of its proper divisors (306180196).

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

218400140 is an equidigital number, since it uses as much as digits as its factorization.

218400140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2514 (or 1263 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

The square root of 218400140 is about 14778.3672981828. The cubic root of 218400140 is about 602.2141708797.

Adding to 218400140 its reverse (41004812), we get a palindrome (259404952).

The spelling of 218400140 in words is "two hundred eighteen million, four hundred thousand, one hundred forty".