20121020022221 has 8 divisors (see below), whose sum is σ = 20137634817144. Its totient is φ = 20104405793280.

The previous prime is 20121020022209. The next prime is 20121020022251. The reversal of 20121020022221 is 12222002012102.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 12955601173321 + 7165418848900 = 3599389^2 + 2676830^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20121020022221 - 2²⁶ = 20120952913357 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20121020022221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121020022251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 100147361 + ... + 100348073.

It is an arithmetic number, because the mean of its divisors is an integer number (2517204352143).

Almost surely, 2^{20121020022221} is an apocalyptic number.

It is an amenable number.

20121020022221 is a deficient number, since it is larger than the sum of its proper divisors (16614794923).

20121020022221 is a wasteful number, since it uses less digits than its factorization.

20121020022221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282991.

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

Adding to 20121020022221 its reverse (12222002012102), we get a palindrome (32343022034323).

The spelling of 20121020022221 in words is "twenty trillion, one hundred twenty-one billion, twenty million, twenty-two thousand, two hundred twenty-one".