200121022102021 has 4 divisors (see below), whose sum is σ = 200122660559500. Its totient is φ = 200119383644544.

The previous prime is 200121022102013. The next prime is 200121022102063. The reversal of 200121022102021 is 120201220121002.

It is a happy number.

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 142008072557796 + 58112949544225 = 11916714^2 + 7623185^2 .

It is a cyclic number.

It is not a de Polignac number, because 200121022102021 - 2³ = 200121022102013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 200121022101986 and 200121022102004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (200121022102921) 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, 819045516 + ... + 819289813.

It is an arithmetic number, because the mean of its divisors is an integer number (50030665139875).

Almost surely, 2^{200121022102021} is an apocalyptic number.

It is an amenable number.

200121022102021 is a deficient number, since it is larger than the sum of its proper divisors (1638457479).

200121022102021 is a wasteful number, since it uses less digits than its factorization.

200121022102021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1638457478.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 200121022102021 its reverse (120201220121002), we get a palindrome (320322242223023).

The spelling of 200121022102021 in words is "two hundred trillion, one hundred twenty-one billion, twenty-two million, one hundred two thousand, twenty-one".