218728100 has 36 divisors (see below), whose sum is σ = 485687664. Its totient is φ = 85454880.

The previous prime is 218728049. The next prime is 218728117. The reversal of 218728100 is 1827812.

It is a super-2 number, since 2×218728100² = 95683963459220000, which contains 22 as substring.

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 11 ways as a sum of consecutive naturals, for example, 21134 + ... + 29733.

It is an arithmetic number, because the mean of its divisors is an integer number (13491324).

Almost surely, 2^218728100 is an apocalyptic number.

218728100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

218728100 is an abundant number, since it is smaller than the sum of its proper divisors (266959564).

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

218728100 is a wasteful number, since it uses less digits than its factorization.

218728100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50924 (or 50917 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 29.

The square root of 218728100 is about 14789.4590840909. The cubic root of 218728100 is about 602.5154579002.

The spelling of 218728100 in words is "two hundred eighteen million, seven hundred twenty-eight thousand, one hundred".