221147212 has 24 divisors (see below), whose sum is σ = 454667472. Its totient is φ = 92788800.

The previous prime is 221147209. The next prime is 221147219. The reversal of 221147212 is 212741122.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is not an unprimeable number, because it can be changed into a prime (221147219) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 192739 + ... + 193882.

It is an arithmetic number, because the mean of its divisors is an integer number (18944478).

Almost surely, 2^221147212 is an apocalyptic number.

221147212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

221147212 is an abundant number, since it is smaller than the sum of its proper divisors (233520260).

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

221147212 is a wasteful number, since it uses less digits than its factorization.

221147212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 386649 (or 386647 counting only the distinct ones).

The product of its digits is 448, while the sum is 22.

The square root of 221147212 is about 14871.0191984275. The cubic root of 221147212 is about 604.7285734623.

Adding to 221147212 its reverse (212741122), we get a palindrome (433888334).

The spelling of 221147212 in words is "two hundred twenty-one million, one hundred forty-seven thousand, two hundred twelve".