221212112 has 20 divisors (see below), whose sum is σ = 467562336. Its totient is φ = 100550880.

The previous prime is 221212111. The next prime is 221212129. The reversal of 221212112 is 211212122.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221212111) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 628268 + ... + 628619.

Almost surely, 2^221212112 is an apocalyptic number.

221212112 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

221212112 is an abundant number, since it is smaller than the sum of its proper divisors (246350224).

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

221212112 is a wasteful number, since it uses less digits than its factorization.

221212112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1256906 (or 1256900 counting only the distinct ones).

The product of its digits is 32, while the sum is 14.

The square root of 221212112 is about 14873.2011349272. The cubic root of 221212112 is about 604.7877241753.

Adding to 221212112 its reverse (211212122), we get a palindrome (432424234).

The spelling of 221212112 in words is "two hundred twenty-one million, two hundred twelve thousand, one hundred twelve".