101211111221221 has 4 divisors (see below), whose sum is σ = 101211575461452. Its totient is φ = 101210646980992.

The previous prime is 101211111221219. The next prime is 101211111221251. The reversal of 101211111221221 is 122122111112101.

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 96926683168225 + 4284428052996 = 9845135^2 + 2069886^2 .

It is a cyclic number.

It is not a de Polignac number, because 101211111221221 - 2¹ = 101211111221219 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101211111221201) 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, 231792940 + ... + 232229173.

It is an arithmetic number, because the mean of its divisors is an integer number (25302893865363).

Almost surely, 2^{101211111221221} is an apocalyptic number.

It is an amenable number.

101211111221221 is a deficient number, since it is larger than the sum of its proper divisors (464240231).

101211111221221 is an equidigital number, since it uses as much as digits as its factorization.

101211111221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 464240230.

The product of its (nonzero) digits is 32, while the sum is 19.

Adding to 101211111221221 its reverse (122122111112101), we get a palindrome (223333222333322).

The spelling of 101211111221221 in words is "one hundred one trillion, two hundred eleven billion, one hundred eleven million, two hundred twenty-one thousand, two hundred twenty-one".