218404180 has 12 divisors (see below), whose sum is σ = 458648820. Its totient is φ = 87361664.

The previous prime is 218404177. The next prime is 218404213. The reversal of 218404180 is 81404812.

It can be written as a sum of positive squares in 2 ways, for example, as 51581124 + 166823056 = 7182^2 + 12916^2 .

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 3 ways as a sum of consecutive naturals, for example, 5460085 + ... + 5460124.

It is an arithmetic number, because the mean of its divisors is an integer number (38220735).

Almost surely, 2^218404180 is an apocalyptic number.

218404180 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

218404180 is an abundant number, since it is smaller than the sum of its proper divisors (240244640).

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

218404180 is a wasteful number, since it uses less digits than its factorization.

218404180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10920218 (or 10920216 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 28.

The square root of 218404180 is about 14778.5039838273. The cubic root of 218404180 is about 602.2178841408.

Adding to 218404180 its reverse (81404812), we get a palindrome (299808992).

It can be divided in two parts, 21 and 8404180, that added together give a square (8404201 = 2899²).

The spelling of 218404180 in words is "two hundred eighteen million, four hundred four thousand, one hundred eighty".