20121102012221 has 16 divisors (see below), whose sum is σ = 24354821462400. Its totient is φ = 16227751403520.

The previous prime is 20121102012217. The next prime is 20121102012247. The reversal of 20121102012221 is 12221020112102.

It is a cyclic number.

It is not a de Polignac number, because 20121102012221 - 2² = 20121102012217 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (17).

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 20121102012221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121102012281) 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, 22465796 + ... + 23344253.

It is an arithmetic number, because the mean of its divisors is an integer number (1522176341400).

Almost surely, 2^{20121102012221} is an apocalyptic number.

It is an amenable number.

20121102012221 is a deficient number, since it is larger than the sum of its proper divisors (4233719450179).

20121102012221 is a wasteful number, since it uses less digits than its factorization.

20121102012221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45813764.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 20121102012221 its reverse (12221020112102), we get a palindrome (32342122124323).

The spelling of 20121102012221 in words is "twenty trillion, one hundred twenty-one billion, one hundred two million, twelve thousand, two hundred twenty-one".