20001221021222 has 32 divisors (see below), whose sum is σ = 34320958543872. Its totient is φ = 8563665045024.

The previous prime is 20001221021219. The next prime is 20001221021267. The reversal of 20001221021222 is 22212012210002.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 20001221021222.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 370936208 + ... + 370990124.

It is an arithmetic number, because the mean of its divisors is an integer number (1072529954496).

Almost surely, 2^{20001221021222} is an apocalyptic number.

20001221021222 is a deficient number, since it is larger than the sum of its proper divisors (14319737522650).

20001221021222 is a wasteful number, since it uses less digits than its factorization.

20001221021222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79052.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 20001221021222 its reverse (22212012210002), we get a palindrome (42213233231224).

The spelling of 20001221021222 in words is "twenty trillion, one billion, two hundred twenty-one million, twenty-one thousand, two hundred twenty-two".