221951232 has 144 divisors (see below), whose sum is σ = 663727680. Its totient is φ = 73156608.

The previous prime is 221951207. The next prime is 221951243. The reversal of 221951232 is 232159122.

It is a happy number.

221951232 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 221951196 and 221951205.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1126558 + ... + 1126754.

It is an arithmetic number, because the mean of its divisors is an integer number (4609220).

Almost surely, 2^221951232 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 221951232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (331863840).

221951232 is an abundant number, since it is smaller than the sum of its proper divisors (441776448).

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

221951232 is a wasteful number, since it uses less digits than its factorization.

221951232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385 (or 365 counting only the distinct ones).

The product of its digits is 2160, while the sum is 27.

The square root of 221951232 is about 14898.0277889390. The cubic root of 221951232 is about 605.4605531718.

The spelling of 221951232 in words is "two hundred twenty-one million, nine hundred fifty-one thousand, two hundred thirty-two".