221221252 has 12 divisors (see below), whose sum is σ = 442442560. Its totient is φ = 94809096.

The previous prime is 221221249. The next prime is 221221327. The reversal of 221221252 is 252122122.

221221252 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3950352 + ... + 3950407.

Almost surely, 2^221221252 is an apocalyptic number.

It is an amenable number.

221221252 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

221221252 is a wasteful number, since it uses less digits than its factorization.

221221252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7900770 (or 7900768 counting only the distinct ones).

The product of its digits is 320, while the sum is 19.

The square root of 221221252 is about 14873.5083958022. The cubic root of 221221252 is about 604.7960535620.

Adding to 221221252 its reverse (252122122), we get a palindrome (473343374).

The spelling of 221221252 in words is "two hundred twenty-one million, two hundred twenty-one thousand, two hundred fifty-two".