21201211324441 has 4 divisors (see below), whose sum is σ = 21308831686692. Its totient is φ = 21093590962192.

The previous prime is 21201211324387. The next prime is 21201211324459. The reversal of 21201211324441 is 14442311210212.

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 17052233419225 + 4148977905216 = 4129435^2 + 2036904^2 .

It is a cyclic number.

It is not a de Polignac number, because 21201211324441 - 2⁷ = 21201211324313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21201211324481) 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, 53810180830 + ... + 53810181223.

It is an arithmetic number, because the mean of its divisors is an integer number (5327207921673).

Almost surely, 2^{21201211324441} is an apocalyptic number.

It is an amenable number.

21201211324441 is a deficient number, since it is larger than the sum of its proper divisors (107620362251).

21201211324441 is a wasteful number, since it uses less digits than its factorization.

21201211324441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107620362250.

The product of its (nonzero) digits is 3072, while the sum is 28.

Adding to 21201211324441 its reverse (14442311210212), we get a palindrome (35643522534653).

The spelling of 21201211324441 in words is "twenty-one trillion, two hundred one billion, two hundred eleven million, three hundred twenty-four thousand, four hundred forty-one".