221773212 has 72 divisors (see below), whose sum is σ = 574108080. Its totient is φ = 72161280.

The previous prime is 221773193. The next prime is 221773217. The reversal of 221773212 is 212377122.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221773217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 409662 + ... + 410202.

Almost surely, 2^221773212 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 221773212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (287054040).

221773212 is an abundant number, since it is smaller than the sum of its proper divisors (352334868).

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

221773212 is a wasteful number, since it uses less digits than its factorization.

221773212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 803 (or 798 counting only the distinct ones).

The product of its digits is 2352, while the sum is 27.

The square root of 221773212 is about 14892.0519741236. The cubic root of 221773212 is about 605.2986363454.

The spelling of 221773212 in words is "two hundred twenty-one million, seven hundred seventy-three thousand, two hundred twelve".