221622656 has 32 divisors (see below), whose sum is σ = 444917880. Its totient is φ = 109957120.

The previous prime is 221622647. The next prime is 221622683. The reversal of 221622656 is 656226122.

It is a tau number, because it is divible by the number of its divisors (32).

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10160 + ... + 23376.

Almost surely, 2^221622656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221622656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (222458940).

221622656 is an abundant number, since it is smaller than the sum of its proper divisors (223295224).

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

221622656 is a wasteful number, since it uses less digits than its factorization.

221622656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13362 (or 13350 counting only the distinct ones).

The product of its digits is 17280, while the sum is 32.

The square root of 221622656 is about 14886.9962047419. The cubic root of 221622656 is about 605.1616315637.

Adding to 221622656 its reverse (656226122), we get a palindrome (877848778).

The spelling of 221622656 in words is "two hundred twenty-one million, six hundred twenty-two thousand, six hundred fifty-six".