216505500 has 192 divisors, whose sum is σ = 669247488. Its totient is φ = 54316800.

The previous prime is 216505481. The next prime is 216505511. The reversal of 216505500 is 5505612.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2608459 + ... + 2608541.

It is an arithmetic number, because the mean of its divisors is an integer number (3485664).

Almost surely, 2^216505500 is an apocalyptic number.

216505500 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 216505500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (334623744).

216505500 is an abundant number, since it is smaller than the sum of its proper divisors (452741988).

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

216505500 is a wasteful number, since it uses less digits than its factorization.

216505500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 189 (or 177 counting only the distinct ones).

The product of its (nonzero) digits is 1500, while the sum is 24.

The square root of 216505500 is about 14714.1258659833. The cubic root of 216505500 is about 600.4676909029.

The spelling of 216505500 in words is "two hundred sixteen million, five hundred five thousand, five hundred".