221021112121021 has 8 divisors (see below), whose sum is σ = 221038778498688. Its totient is φ = 221003446500000.

The previous prime is 221021112121009. The next prime is 221021112121081. The reversal of 221021112121021 is 120121211120122.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221021112121021 - 2³³ = 221012522186429 is a prime.

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 221021112121021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221021112121001) 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 7 ways as a sum of consecutive naturals, for example, 677294146 + ... + 677620396.

It is an arithmetic number, because the mean of its divisors is an integer number (27629847312336).

Almost surely, 2^{221021112121021} is an apocalyptic number.

It is an amenable number.

221021112121021 is a deficient number, since it is larger than the sum of its proper divisors (17666377667).

221021112121021 is a wasteful number, since it uses less digits than its factorization.

221021112121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378323.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 221021112121021 its reverse (120121211120122), we get a palindrome (341142323241143).

The spelling of 221021112121021 in words is "two hundred twenty-one trillion, twenty-one billion, one hundred twelve million, one hundred twenty-one thousand, twenty-one".