21201120121201 has 8 divisors (see below), whose sum is σ = 21718367785800. Its totient is φ = 20683879464960.

The previous prime is 21201120121157. The next prime is 21201120121213. The reversal of 21201120121201 is 10212102110212.

It can be written as a sum of positive squares in 4 ways, for example, as 746521920225 + 20454598200976 = 864015^2 + 4522676^2 .

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 21201120121201 - 2¹⁷ = 21201119990129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21201120121261) 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, 4654245 + ... + 8004013.

It is an arithmetic number, because the mean of its divisors is an integer number (2714795973225).

Almost surely, 2^{21201120121201} is an apocalyptic number.

It is an amenable number.

21201120121201 is a deficient number, since it is larger than the sum of its proper divisors (517247664599).

21201120121201 is a wasteful number, since it uses less digits than its factorization.

21201120121201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3504179.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21201120121201 its reverse (10212102110212), we get a palindrome (31413222231413).

The spelling of 21201120121201 in words is "twenty-one trillion, two hundred one billion, one hundred twenty million, one hundred twenty-one thousand, two hundred one".