221648994 has 64 divisors (see below), whose sum is σ = 564756480. Its totient is φ = 63121680.

The previous prime is 221648963. The next prime is 221649013. The reversal of 221648994 is 499846122.

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, 144009 + ... + 145539.

It is an arithmetic number, because the mean of its divisors is an integer number (8824320).

Almost surely, 2^221648994 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221648994, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (282378240).

221648994 is an abundant number, since it is smaller than the sum of its proper divisors (343107486).

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

221648994 is a wasteful number, since it uses less digits than its factorization.

221648994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1932 (or 1926 counting only the distinct ones).

The product of its digits is 248832, while the sum is 45.

The square root of 221648994 is about 14887.8807759869. The cubic root of 221648994 is about 605.1856034145.

The spelling of 221648994 in words is "two hundred twenty-one million, six hundred forty-eight thousand, nine hundred ninety-four".