221216000 has 144 divisors (see below), whose sum is σ = 571404288. Its totient is φ = 85248000.

The previous prime is 221215991. The next prime is 221216003. The reversal of 221216000 is 612122.

221216000 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221216003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 991889 + ... + 992111.

Almost surely, 2^221216000 is an apocalyptic number.

221216000 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 221216000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (285702144).

221216000 is an abundant number, since it is smaller than the sum of its proper divisors (350188288).

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

221216000 is an equidigital number, since it uses as much as digits as its factorization.

221216000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285 (or 261 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 221216000 is about 14873.3318392349. The cubic root of 221216000 is about 604.7912673823.

Adding to 221216000 its reverse (612122), we get a palindrome (221828122).

The spelling of 221216000 in words is "two hundred twenty-one million, two hundred sixteen thousand".