11221121210021 has 4 divisors (see below), whose sum is σ = 11221319909100. Its totient is φ = 11220922510944.

The previous prime is 11221121210009. The next prime is 11221121210041. The reversal of 11221121210021 is 12001212112211.

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 6802780269796 + 4418340940225 = 2608214^2 + 2101985^2 .

It is a cyclic number.

It is not a de Polignac number, because 11221121210021 - 2¹⁴ = 11221121193637 is a prime.

It is a super-2 number, since 2×11221121210021² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11221121210041) 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, 99264806 + ... + 99377783.

It is an arithmetic number, because the mean of its divisors is an integer number (2805329977275).

Almost surely, 2^{11221121210021} is an apocalyptic number.

It is an amenable number.

11221121210021 is a deficient number, since it is larger than the sum of its proper divisors (198699079).

11221121210021 is an equidigital number, since it uses as much as digits as its factorization.

11221121210021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198699078.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 11221121210021 its reverse (12001212112211), we get a palindrome (23222333322232).

The spelling of 11221121210021 in words is "eleven trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred ten thousand, twenty-one".