20112121021221 has 24 divisors (see below), whose sum is σ = 29218043181600. Its totient is φ = 13331132103456.

The previous prime is 20112121021171. The next prime is 20112121021253. The reversal of 20112121021221 is 12212012121102.

20112121021221 is a `hidden beast` number, since 201 + 1 + 21 + 210 + 212 + 21 = 666.

It is not a de Polignac number, because 20112121021221 - 2⁷ = 20112121021093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20112121021194 and 20112121021203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20112121021261) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8136435 + ... + 10316288.

It is an arithmetic number, because the mean of its divisors is an integer number (1217418465900).

Almost surely, 2^{20112121021221} is an apocalyptic number.

It is an amenable number.

20112121021221 is a deficient number, since it is larger than the sum of its proper divisors (9105922160379).

20112121021221 is a wasteful number, since it uses less digits than its factorization.

20112121021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18453425 (or 18453422 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 20112121021221 its reverse (12212012121102), we get a palindrome (32324133142323).

The spelling of 20112121021221 in words is "twenty trillion, one hundred twelve billion, one hundred twenty-one million, twenty-one thousand, two hundred twenty-one".