21210100201121 has 4 divisors (see below), whose sum is σ = 22841646370452. Its totient is φ = 19578554031792.

The previous prime is 21210100201093. The next prime is 21210100201181. The reversal of 21210100201121 is 12110200101212.

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 819095591521 + 20391004609600 = 905039^2 + 4515640^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21210100201121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21210100201096 and 21210100201105.

It is not an unprimeable number, because it can be changed into a prime (21210100201181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 815773084646 + ... + 815773084671.

It is an arithmetic number, because the mean of its divisors is an integer number (5710411592613).

Almost surely, 2^{21210100201121} is an apocalyptic number.

It is an amenable number.

21210100201121 is a deficient number, since it is larger than the sum of its proper divisors (1631546169331).

21210100201121 is a wasteful number, since it uses less digits than its factorization.

21210100201121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1631546169330.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21210100201121 its reverse (12110200101212), we get a palindrome (33320300302333).

Subtracting from 21210100201121 its reverse (12110200101212), we obtain a palindrome (9099900099909).

The spelling of 21210100201121 in words is "twenty-one trillion, two hundred ten billion, one hundred million, two hundred one thousand, one hundred twenty-one".