218228400 has 180 divisors, whose sum is σ = 815742928. Its totient is φ = 53706240.

The previous prime is 218228383. The next prime is 218228407. The reversal of 218228400 is 4822812.

It is a tau number, because it is divible by the number of its divisors (180).

It is not an unprimeable number, because it can be changed into a prime (218228407) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 44469 + ... + 49131.

Almost surely, 2^218228400 is an apocalyptic number.

218228400 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 218228400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (407871464).

218228400 is an abundant number, since it is smaller than the sum of its proper divisors (597514528).

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

218228400 is a wasteful number, since it uses less digits than its factorization.

218228400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4700 (or 4686 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 218228400 is about 14772.5556353665. Note that the first 3 decimals coincide. The cubic root of 218228400 is about 602.0562781498.

The spelling of 218228400 in words is "two hundred eighteen million, two hundred twenty-eight thousand, four hundred".