20011021211121 has 8 divisors (see below), whose sum is σ = 26683182553920. Its totient is φ = 13339770337872.

The previous prime is 20011021211119. The next prime is 20011021211123. The reversal of 20011021211121 is 12111212011002.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20011021211119) and next prime (20011021211123).

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

It is not a de Polignac number, because 20011021211121 - 2¹ = 20011021211119 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20011021211121.

It is not an unprimeable number, because it can be changed into a prime (20011021211123) 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, 227566101 + ... + 227654018.

It is an arithmetic number, because the mean of its divisors is an integer number (3335397819240).

Almost surely, 2^{20011021211121} is an apocalyptic number.

It is an amenable number.

20011021211121 is a deficient number, since it is larger than the sum of its proper divisors (6672161342799).

20011021211121 is a wasteful number, since it uses less digits than its factorization.

20011021211121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 455234775.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 20011021211121 its reverse (12111212011002), we get a palindrome (32122233222123).

The spelling of 20011021211121 in words is "twenty trillion, eleven billion, twenty-one million, two hundred eleven thousand, one hundred twenty-one".