221213212209 has 48 divisors (see below), whose sum is σ = 349950706560. Its totient is φ = 133541498880.

The previous prime is 221213212193. The next prime is 221213212211. The reversal of 221213212209 is 902212312122.

221213212209 is a `hidden beast` number, since 221 + 21 + 3 + 212 + 209 = 666.

221213212209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221213212209 - 2⁴ = 221213212193 is a prime.

It is a super-3 number, since 3×221213212209³ (a number of 35 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (221213213209) 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 47 ways as a sum of consecutive naturals, for example, 63988209 + ... + 63991665.

It is an arithmetic number, because the mean of its divisors is an integer number (7290639720).

Almost surely, 2^221213212209 is an apocalyptic number.

It is an amenable number.

221213212209 is a deficient number, since it is larger than the sum of its proper divisors (128737494351).

221213212209 is a wasteful number, since it uses less digits than its factorization.

221213212209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5830 (or 5827 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The spelling of 221213212209 in words is "two hundred twenty-one billion, two hundred thirteen million, two hundred twelve thousand, two hundred nine".