20201220112121 has 2 divisors, whose sum is σ = 20201220112122. Its totient is φ = 20201220112120.

The previous prime is 20201220112103. The next prime is 20201220112127. The reversal of 20201220112121 is 12121102210202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17478921408400 + 2722298703721 = 4180780^2 + 1649939^2 .

It is a cyclic number.

It is not a de Polignac number, because 20201220112121 - 2¹⁴ = 20201220095737 is a prime.

It is a super-2 number, since 2×20201220112121² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20201220112121.

It is not a weakly prime, because it can be changed into another prime (20201220112127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10100610056060 + 10100610056061.

It is an arithmetic number, because the mean of its divisors is an integer number (10100610056061).

Almost surely, 2^{20201220112121} is an apocalyptic number.

It is an amenable number.

20201220112121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20201220112121 is an equidigital number, since it uses as much as digits as its factorization.

20201220112121 is an evil number, because the sum of its binary digits is even.

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

Adding to 20201220112121 its reverse (12121102210202), we get a palindrome (32322322322323).

The spelling of 20201220112121 in words is "twenty trillion, two hundred one billion, two hundred twenty million, one hundred twelve thousand, one hundred twenty-one".