21000020221222 has 32 divisors (see below), whose sum is σ = 37257123928320. Its totient is φ = 8685998163360.

The previous prime is 21000020221163. The next prime is 21000020221223. The reversal of 21000020221222 is 22212202000012.

It is a junction number, because it is equal to n+sod(n) for n = 21000020221196 and 21000020221205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000020221223) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9945048 + ... + 11870299.

It is an arithmetic number, because the mean of its divisors is an integer number (1164285122760).

Almost surely, 2^{21000020221222} is an apocalyptic number.

21000020221222 is a deficient number, since it is larger than the sum of its proper divisors (16257103707098).

21000020221222 is a wasteful number, since it uses less digits than its factorization.

21000020221222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21817756.

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 21000020221222 its reverse (22212202000012), we get a palindrome (43212222221234).

The spelling of 21000020221222 in words is "twenty-one trillion, twenty million, two hundred twenty-one thousand, two hundred twenty-two".