221102021220121 has 4 divisors (see below), whose sum is σ = 226494753445044. Its totient is φ = 215709288995200.

The previous prime is 221102021220089. The next prime is 221102021220127. The reversal of 221102021220121 is 121022120201122.

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 3166481450521 + 217935539769600 = 1779461^2 + 14762640^2 .

It is a cyclic number.

It is not a de Polignac number, because 221102021220121 - 2⁵ = 221102021220089 is a prime.

It is a super-2 number, since 2×221102021220121² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221102021220127) 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, 2696366112400 + ... + 2696366112481.

It is an arithmetic number, because the mean of its divisors is an integer number (56623688361261).

Almost surely, 2^{221102021220121} is an apocalyptic number.

It is an amenable number.

221102021220121 is a deficient number, since it is larger than the sum of its proper divisors (5392732224923).

221102021220121 is an equidigital number, since it uses as much as digits as its factorization.

221102021220121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5392732224922.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 221102021220121 its reverse (121022120201122), we get a palindrome (342124141421243).

The spelling of 221102021220121 in words is "two hundred twenty-one trillion, one hundred two billion, twenty-one million, two hundred twenty thousand, one hundred twenty-one".