216500000 has 84 divisors (see below), whose sum is σ = 534016602. Its totient is φ = 86400000.

The previous prime is 216499999. The next prime is 216500021. The reversal of 216500000 is 5612.

It can be written as a sum of positive squares in 7 ways, for example, as 161086864 + 55413136 = 12692^2 + 7444^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 499784 + ... + 500216.

Almost surely, 2^216500000 is an apocalyptic number.

216500000 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 216500000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (267008301).

216500000 is an abundant number, since it is smaller than the sum of its proper divisors (317516602).

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

216500000 is an frugal number, since it uses more digits than its factorization.

216500000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 473 (or 440 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 216500000 is about 14713.9389695622. The cubic root of 216500000 is about 600.4626061971.

Adding to 216500000 its reverse (5612), we get a palindrome (216505612).

The spelling of 216500000 in words is "two hundred sixteen million, five hundred thousand".