216841240 has 128 divisors (see below), whose sum is σ = 634936320. Its totient is φ = 64627200.

The previous prime is 216841231. The next prime is 216841241. The reversal of 216841240 is 42148612.

216841240 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 216841199 and 216841208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216841241) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 69310 + ... + 72370.

It is an arithmetic number, because the mean of its divisors is an integer number (4960440).

Almost surely, 2^216841240 is an apocalyptic number.

216841240 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 216841240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (317468160).

216841240 is an abundant number, since it is smaller than the sum of its proper divisors (418095080).

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

216841240 is a wasteful number, since it uses less digits than its factorization.

216841240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3113 (or 3109 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 28.

The square root of 216841240 is about 14725.5302111673. The cubic root of 216841240 is about 600.7779168989. Note that the first 3 decimals are identical.

Adding to 216841240 its reverse (42148612), we get a palindrome (258989852).

The spelling of 216841240 in words is "two hundred sixteen million, eight hundred forty-one thousand, two hundred forty".