218978100 has 288 divisors, whose sum is σ = 786199680. Its totient is φ = 51840000.

The previous prime is 218978083. The next prime is 218978107. The reversal of 218978100 is 1879812.

218978100 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×218978100² = 95902816559220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218978107) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2168050 + ... + 2168150.

It is an arithmetic number, because the mean of its divisors is an integer number (2729860).

Almost surely, 2^218978100 is an apocalyptic number.

218978100 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 218978100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (393099840).

218978100 is an abundant number, since it is smaller than the sum of its proper divisors (567221580).

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

218978100 is a wasteful number, since it uses less digits than its factorization.

218978100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208 (or 195 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 36.

The square root of 218978100 is about 14797.9086360202. The cubic root of 218978100 is about 602.7449231780.

The spelling of 218978100 in words is "two hundred eighteen million, nine hundred seventy-eight thousand, one hundred".