20012021220121 has 12 divisors (see below), whose sum is σ = 23301230946660. Its totient is φ = 17136994025760.

The previous prime is 20012021220089. The next prime is 20012021220133. The reversal of 20012021220121 is 12102212021002.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 16417447904025 + 3594573316096 = 4051845^2 + 1895936^2 .

It is not a de Polignac number, because 20012021220121 - 2⁵ = 20012021220089 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20012021220095 and 20012021220104.

It is not an unprimeable number, because it can be changed into a prime (20012021221121) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 192412006 + ... + 192515983.

It is an arithmetic number, because the mean of its divisors is an integer number (1941769245555).

Almost surely, 2^{20012021220121} is an apocalyptic number.

It is an amenable number.

20012021220121 is a deficient number, since it is larger than the sum of its proper divisors (3289209726539).

20012021220121 is a wasteful number, since it uses less digits than its factorization.

20012021220121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384929064 (or 384929057 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 20012021220121 its reverse (12102212021002), we get a palindrome (32114233241123).

The spelling of 20012021220121 in words is "twenty trillion, twelve billion, twenty-one million, two hundred twenty thousand, one hundred twenty-one".