221118000 has 160 divisors (see below), whose sum is σ = 720757440. Its totient is φ = 58316800.

The previous prime is 221117983. The next prime is 221118013. The reversal of 221118000 is 811122.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 821866 + ... + 822134.

It is an arithmetic number, because the mean of its divisors is an integer number (4504734).

Almost surely, 2^221118000 is an apocalyptic number.

221118000 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 221118000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (360378720).

221118000 is an abundant number, since it is smaller than the sum of its proper divisors (499639440).

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

221118000 is a wasteful number, since it uses less digits than its factorization.

221118000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432 (or 416 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

The square root of 221118000 is about 14870.0369871766. The cubic root of 221118000 is about 604.7019454848.

Adding to 221118000 its reverse (811122), we get a palindrome (221929122).

The spelling of 221118000 in words is "two hundred twenty-one million, one hundred eighteen thousand".