218581416 has 96 divisors (see below), whose sum is σ = 617853600. Its totient is φ = 72394560.

The previous prime is 218581379. The next prime is 218581417. The reversal of 218581416 is 614185812.

218581416 = T₁₁₃ + T₁₁₄ + ... + T₁₀₉₄.

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

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (218581417) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 444931 + ... + 445421.

It is an arithmetic number, because the mean of its divisors is an integer number (6435975).

Almost surely, 2^218581416 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 218581416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (308926800).

218581416 is an abundant number, since it is smaller than the sum of its proper divisors (399272184).

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

218581416 is a wasteful number, since it uses less digits than its factorization.

218581416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 741 (or 725 counting only the distinct ones).

The product of its digits is 15360, while the sum is 36.

The square root of 218581416 is about 14784.4991798843. The cubic root of 218581416 is about 602.3807409598.

218581416 divided by its sum of digits (36) gives a palindrome (6071706).

The spelling of 218581416 in words is "two hundred eighteen million, five hundred eighty-one thousand, four hundred sixteen".