216221850 has 144 divisors (see below), whose sum is σ = 653208192. Its totient is φ = 50878080.

The previous prime is 216221849. The next prime is 216221857. The reversal of 216221850 is 58122612.

It is a happy number.

216221850 is a `hidden beast` number, since 21 + 622 + 18 + 5 + 0 = 666.

216221850 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (216221857) by changing a digit.

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 71 ways as a sum of consecutive naturals, for example, 133747 + ... + 135353.

It is an arithmetic number, because the mean of its divisors is an integer number (4536168).

Almost surely, 2^216221850 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 216221850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (326604096).

216221850 is an abundant number, since it is smaller than the sum of its proper divisors (436986342).

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

216221850 is a wasteful number, since it uses less digits than its factorization.

216221850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1661 (or 1653 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 216221850 is about 14704.4840099882. The cubic root of 216221850 is about 600.2053463801.

The spelling of 216221850 in words is "two hundred sixteen million, two hundred twenty-one thousand, eight hundred fifty".