10121121111221 has 4 divisors (see below), whose sum is σ = 10470125287500. Its totient is φ = 9772116934944.

The previous prime is 10121121111203. The next prime is 10121121111247. The reversal of 10121121111221 is 12211112112101.

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 4585636788100 + 5535484323121 = 2141410^2 + 2352761^2 .

It is a cyclic number.

It is not a de Polignac number, because 10121121111221 - 2²⁶ = 10121054002357 is a prime.

It is a super-2 number, since 2×10121121111221² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 10121121111221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10121121111271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 174502088096 + ... + 174502088153.

It is an arithmetic number, because the mean of its divisors is an integer number (2617531321875).

Almost surely, 2^{10121121111221} is an apocalyptic number.

It is an amenable number.

10121121111221 is a deficient number, since it is larger than the sum of its proper divisors (349004176279).

10121121111221 is an equidigital number, since it uses as much as digits as its factorization.

10121121111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 349004176278.

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 10121121111221 its reverse (12211112112101), we get a palindrome (22332233223322).

The spelling of 10121121111221 in words is "ten trillion, one hundred twenty-one billion, one hundred twenty-one million, one hundred eleven thousand, two hundred twenty-one".