10217721121 has 4 divisors (see below), whose sum is σ = 10226584132. Its totient is φ = 10208858112.

The previous prime is 10217721097. The next prime is 10217721127. The reversal of 10217721121 is 12112771201.

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 8360542096 + 1857179025 = 91436^2 + 43095^2 .

It is a cyclic number.

It is not a de Polignac number, because 10217721121 - 2⁹ = 10217720609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (10217721127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4429776 + ... + 4432081.

It is an arithmetic number, because the mean of its divisors is an integer number (2556646033).

Almost surely, 2^10217721121 is an apocalyptic number.

It is an amenable number.

10217721121 is a deficient number, since it is larger than the sum of its proper divisors (8863011).

10217721121 is an equidigital number, since it uses as much as digits as its factorization.

10217721121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8863010.

The product of its (nonzero) digits is 392, while the sum is 25.

The spelling of 10217721121 in words is "ten billion, two hundred seventeen million, seven hundred twenty-one thousand, one hundred twenty-one".