2102021200121 has 4 divisors (see below), whose sum is σ = 2106620809332. Its totient is φ = 2097421590912.

The previous prime is 2102021200109. The next prime is 2102021200189. The reversal of 2102021200121 is 1210021202012.

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 1691133790096 + 410887410025 = 1300436^2 + 641005^2 .

It is a cyclic number.

It is not a de Polignac number, because 2102021200121 - 2¹⁸ = 2102020937977 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2102021200096 and 2102021200105.

It is not an unprimeable number, because it can be changed into a prime (2102021208121) 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, 2299803920 + ... + 2299804833.

It is an arithmetic number, because the mean of its divisors is an integer number (526655202333).

Almost surely, 2^{2102021200121} is an apocalyptic number.

It is an amenable number.

2102021200121 is a deficient number, since it is larger than the sum of its proper divisors (4599609211).

2102021200121 is an equidigital number, since it uses as much as digits as its factorization.

2102021200121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4599609210.

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 2102021200121 its reverse (1210021202012), we get a palindrome (3312042402133).

The spelling of 2102021200121 in words is "two trillion, one hundred two billion, twenty-one million, two hundred thousand, one hundred twenty-one".