21221222021201 has 4 divisors (see below), whose sum is σ = 21905777570304. Its totient is φ = 20536666472100.

The previous prime is 21221222021119. The next prime is 21221222021243. The reversal of 21221222021201 is 10212022212212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21221222021201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21221222021281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 342277774505 + ... + 342277774566.

It is an arithmetic number, because the mean of its divisors is an integer number (5476444392576).

Almost surely, 2^{21221222021201} is an apocalyptic number.

It is an amenable number.

21221222021201 is a deficient number, since it is larger than the sum of its proper divisors (684555549103).

21221222021201 is an equidigital number, since it uses as much as digits as its factorization.

21221222021201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 684555549102.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 21221222021201 its reverse (10212022212212), we get a palindrome (31433244233413).

The spelling of 21221222021201 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twenty-two million, twenty-one thousand, two hundred one".