221221122020111 has 4 divisors (see below), whose sum is σ = 222008385799824. Its totient is φ = 220433858240400.

The previous prime is 221221122020089. The next prime is 221221122020117. The reversal of 221221122020111 is 111020221122122.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221221122020111 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 (221221122020117) 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, 393631889435 + ... + 393631889996.

It is an arithmetic number, because the mean of its divisors is an integer number (55502096449956).

Almost surely, 2^{221221122020111} is an apocalyptic number.

221221122020111 is a deficient number, since it is larger than the sum of its proper divisors (787263779713).

221221122020111 is an equidigital number, since it uses as much as digits as its factorization.

221221122020111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 787263779712.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 221221122020111 its reverse (111020221122122), we get a palindrome (332241343142233).

The spelling of 221221122020111 in words is "two hundred twenty-one trillion, two hundred twenty-one billion, one hundred twenty-two million, twenty thousand, one hundred eleven".