221010100122121 has 4 divisors (see below), whose sum is σ = 226400590369044. Its totient is φ = 215619609875200.

The previous prime is 221010100122101. The next prime is 221010100122143. The reversal of 221010100122121 is 121221001010122.

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 131938786304521 + 89071313817600 = 11486461^2 + 9437760^2 .

It is a cyclic number.

It is not a de Polignac number, because 221010100122121 - 2²⁷ = 221009965904393 is a prime.

It is a super-2 number, since 2×221010100122121² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 221010100122095 and 221010100122104.

It is not an unprimeable number, because it can be changed into a prime (221010100122101) 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, 2695245123400 + ... + 2695245123481.

It is an arithmetic number, because the mean of its divisors is an integer number (56600147592261).

Almost surely, 2^{221010100122121} is an apocalyptic number.

It is an amenable number.

221010100122121 is a deficient number, since it is larger than the sum of its proper divisors (5390490246923).

221010100122121 is an equidigital number, since it uses as much as digits as its factorization.

221010100122121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5390490246922.

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

Adding to 221010100122121 its reverse (121221001010122), we get a palindrome (342231101132243).

The spelling of 221010100122121 in words is "two hundred twenty-one trillion, ten billion, one hundred million, one hundred twenty-two thousand, one hundred twenty-one".