221222121221012 has 18 divisors (see below), whose sum is σ = 408586840235658. Its totient is φ = 104789425840848.

The previous prime is 221222121221011. The next prime is 221222121221039. The reversal of 221222121221012 is 210122121222122.

It can be written as a sum of positive squares in only one way, i.e., 183976561929616 + 37245559291396 = 13563796^2 + 6102914^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221222121221011) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 76600456043 + ... + 76600458930.

It is an arithmetic number, because the mean of its divisors is an integer number (22699268901981).

Almost surely, 2^{221222121221012} is an apocalyptic number.

It is an amenable number.

221222121221012 is a deficient number, since it is larger than the sum of its proper divisors (187364719014646).

221222121221012 is a wasteful number, since it uses less digits than its factorization.

221222121221012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153200915015 (or 153200914994 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 23.

Adding to 221222121221012 its reverse (210122121222122), we get a palindrome (431344242443134).

The spelling of 221222121221012 in words is "two hundred twenty-one trillion, two hundred twenty-two billion, one hundred twenty-one million, two hundred twenty-one thousand, twelve".