21221211212222 has 32 divisors (see below), whose sum is σ = 36600785971200. Its totient is φ = 9039506303520.

The previous prime is 21221211212083. The next prime is 21221211212239. The reversal of 21221211212222 is 22221211212212.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1148972 + ... + 6615327.

It is an arithmetic number, because the mean of its divisors is an integer number (1143774561600).

Almost surely, 2^{21221211212222} is an apocalyptic number.

21221211212222 is a deficient number, since it is larger than the sum of its proper divisors (15379574758978).

21221211212222 is a wasteful number, since it uses less digits than its factorization.

21221211212222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7765496.

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

Adding to 21221211212222 its reverse (22221211212212), we get a palindrome (43442422424434).

The spelling of 21221211212222 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred eleven million, two hundred twelve thousand, two hundred twenty-two".