20211000012221 has 4 divisors (see below), whose sum is σ = 20211050448732. Its totient is φ = 20210949575712.

The previous prime is 20211000012209. The next prime is 20211000012239. The reversal of 20211000012221 is 12221000011202.

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 404672827321 + 19806327184900 = 636139^2 + 4450430^2 .

It is a cyclic number.

It is not a de Polignac number, because 20211000012221 - 2³⁴ = 20193820143037 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20211000012196 and 20211000012205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20211000062221) 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, 24612320 + ... + 25420233.

It is an arithmetic number, because the mean of its divisors is an integer number (5052762612183).

Almost surely, 2^{20211000012221} is an apocalyptic number.

It is an amenable number.

20211000012221 is a deficient number, since it is larger than the sum of its proper divisors (50436511).

20211000012221 is an equidigital number, since it uses as much as digits as its factorization.

20211000012221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50436510.

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

Adding to 20211000012221 its reverse (12221000011202), we get a palindrome (32432000023423).

The spelling of 20211000012221 in words is "twenty trillion, two hundred eleven billion, twelve thousand, two hundred twenty-one".