20100101220121 has 4 divisors (see below), whose sum is σ = 21646262852452. Its totient is φ = 18553939587792.

The previous prime is 20100101220071. The next prime is 20100101220127. The reversal of 20100101220121 is 12102210100102.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1393922616025 + 18706178604096 = 1180645^2 + 4325064^2 .

It is a cyclic number.

It is not a de Polignac number, because 20100101220121 - 2³¹ = 20097953736473 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 1546161632317 = 20100101220121 / (2 + 0 + 1 + 0 + 0 + 1 + 0 + 1 + 2 + 2 + 0 + 1 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20100101220127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 773080816146 + ... + 773080816171.

It is an arithmetic number, because the mean of its divisors is an integer number (5411565713113).

Almost surely, 2^{20100101220121} is an apocalyptic number.

It is an amenable number.

20100101220121 is a deficient number, since it is larger than the sum of its proper divisors (1546161632331).

20100101220121 is a wasteful number, since it uses less digits than its factorization.

20100101220121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1546161632330.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 20100101220121 its reverse (12102210100102), we get a palindrome (32202311320223).

The spelling of 20100101220121 in words is "twenty trillion, one hundred billion, one hundred one million, two hundred twenty thousand, one hundred twenty-one".