21200313212021 has 4 divisors (see below), whose sum is σ = 21261059095500. Its totient is φ = 21139567328544.

The previous prime is 21200313212011. The next prime is 21200313212053. The reversal of 21200313212021 is 12021231300212.

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 19156597080625 + 2043716131396 = 4376825^2 + 1429586^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21200313212021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21200313211984 and 21200313212002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200313212011) 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, 30372941216 + ... + 30372941913.

It is an arithmetic number, because the mean of its divisors is an integer number (5315264773875).

Almost surely, 2^{21200313212021} is an apocalyptic number.

It is an amenable number.

21200313212021 is a deficient number, since it is larger than the sum of its proper divisors (60745883479).

21200313212021 is an equidigital number, since it uses as much as digits as its factorization.

21200313212021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60745883478.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 21200313212021 its reverse (12021231300212), we get a palindrome (33221544512233).

The spelling of 21200313212021 in words is "twenty-one trillion, two hundred billion, three hundred thirteen million, two hundred twelve thousand, twenty-one".