221089506 has 48 divisors (see below), whose sum is σ = 488490912. Its totient is φ = 66658240.

The previous prime is 221089493. The next prime is 221089513. The reversal of 221089506 is 605980122.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 168505 + ... + 169811.

It is an arithmetic number, because the mean of its divisors is an integer number (10176894).

Almost surely, 2^221089506 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221089506, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (244245456).

221089506 is an abundant number, since it is smaller than the sum of its proper divisors (267401406).

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

221089506 is a wasteful number, since it uses less digits than its factorization.

221089506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1567 (or 1556 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 33.

The square root of 221089506 is about 14869.0788551275. The cubic root of 221089506 is about 604.6759697352.

The spelling of 221089506 in words is "two hundred twenty-one million, eighty-nine thousand, five hundred six".