221121122021111 has 4 divisors (see below), whose sum is σ = 238130439099672. Its totient is φ = 204111804942552.

The previous prime is 221121122021101. The next prime is 221121122021167. The reversal of 221121122021111 is 111120221121122.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 221121122021111 - 2³⁰ = 221120048279287 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 (221121122021101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8504658539261 + ... + 8504658539286.

It is an arithmetic number, because the mean of its divisors is an integer number (59532609774918).

Almost surely, 2^{221121122021111} is an apocalyptic number.

221121122021111 is a deficient number, since it is larger than the sum of its proper divisors (17009317078561).

221121122021111 is a wasteful number, since it uses less digits than its factorization.

221121122021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17009317078560.

The product of its (nonzero) digits is 64, while the sum is 20.

Adding to 221121122021111 its reverse (111120221121122), we get a palindrome (332241343142233).

The spelling of 221121122021111 in words is "two hundred twenty-one trillion, one hundred twenty-one billion, one hundred twenty-two million, twenty-one thousand, one hundred eleven".