221312212 has 12 divisors (see below), whose sum is σ = 422505216. Its totient is φ = 100596440.

The previous prime is 221312191. The next prime is 221312243. The reversal of 221312212 is 212213122.

It is a happy number.

221312212 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, 2514868 + ... + 2514955.

It is an arithmetic number, because the mean of its divisors is an integer number (35208768).

Almost surely, 2^221312212 is an apocalyptic number.

221312212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

221312212 is a deficient number, since it is larger than the sum of its proper divisors (201193004).

221312212 is a wasteful number, since it uses less digits than its factorization.

221312212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5029838 (or 5029836 counting only the distinct ones).

The product of its digits is 96, while the sum is 16.

The square root of 221312212 is about 14876.5658671617. The cubic root of 221312212 is about 604.8789339520.

Adding to 221312212 its reverse (212213122), we get a palindrome (433525334).

The spelling of 221312212 in words is "two hundred twenty-one million, three hundred twelve thousand, two hundred twelve".