20012200221221 has 16 divisors (see below), whose sum is σ = 21601633460400. Its totient is φ = 18429922344960.

The previous prime is 20012200221217. The next prime is 20012200221227. The reversal of 20012200221221 is 12212200221002.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 2049979650625 + 17962220570596 = 1431775^2 + 4238186^2 .

It is a cyclic number.

It is not a de Polignac number, because 20012200221221 - 2² = 20012200221217 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20012200221221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20012200221227) 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, 64010201 + ... + 64322081.

It is an arithmetic number, because the mean of its divisors is an integer number (1350102091275).

Almost surely, 2^{20012200221221} is an apocalyptic number.

It is an amenable number.

20012200221221 is a deficient number, since it is larger than the sum of its proper divisors (1589433239179).

20012200221221 is a wasteful number, since it uses less digits than its factorization.

20012200221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 323336.

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

Adding to 20012200221221 its reverse (12212200221002), we get a palindrome (32224400442223).

The spelling of 20012200221221 in words is "twenty trillion, twelve billion, two hundred million, two hundred twenty-one thousand, two hundred twenty-one".