21210210220201 has 8 divisors (see below), whose sum is σ = 21625467349640. Its totient is φ = 20798965237248.

The previous prime is 21210210220159. The next prime is 21210210220217. The reversal of 21210210220201 is 10202201201212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6178460893801 + 15031749326400 = 2485651^2 + 3877080^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21210210220201 - 2¹⁵ = 21210210187433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21210210220231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1003025946 + ... + 1003047091.

It is an arithmetic number, because the mean of its divisors is an integer number (2703183418705).

Almost surely, 2^{21210210220201} is an apocalyptic number.

It is an amenable number.

21210210220201 is a deficient number, since it is larger than the sum of its proper divisors (415257129439).

21210210220201 is a wasteful number, since it uses less digits than its factorization.

21210210220201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2006073243.

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

Adding to 21210210220201 its reverse (10202201201212), we get a palindrome (31412411421413).

The spelling of 21210210220201 in words is "twenty-one trillion, two hundred ten billion, two hundred ten million, two hundred twenty thousand, two hundred one".