20011220021121 has 24 divisors (see below), whose sum is σ = 31041156272544. Its totient is φ = 11433750269760.

The previous prime is 20011220021119. The next prime is 20011220021171. The reversal of 20011220021121 is 12112002211002.

It is not a de Polignac number, because 20011220021121 - 2¹ = 20011220021119 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20011220021121.

It is not an unprimeable number, because it can be changed into a prime (20011220021171) 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, 5967660 + ... + 8696861.

It is an arithmetic number, because the mean of its divisors is an integer number (1293381511356).

Almost surely, 2^{20011220021121} is an apocalyptic number.

20011220021121 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20011220021121 is a deficient number, since it is larger than the sum of its proper divisors (11029936251423).

20011220021121 is a wasteful number, since it uses less digits than its factorization.

20011220021121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14673821 (or 14673814 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 20011220021121 its reverse (12112002211002), we get a palindrome (32123222232123).

The spelling of 20011220021121 in words is "twenty trillion, eleven billion, two hundred twenty million, twenty-one thousand, one hundred twenty-one".