221211020111111 has 4 divisors (see below), whose sum is σ = 222952839167232. Its totient is φ = 219469201054992.

The previous prime is 221211020111069. The next prime is 221211020111117. The reversal of 221211020111111 is 111111020112122.

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-221211020111111 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 221211020111111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221211020111117) 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, 870909527870 + ... + 870909528123.

It is an arithmetic number, because the mean of its divisors is an integer number (55738209791808).

Almost surely, 2^{221211020111111} is an apocalyptic number.

221211020111111 is a deficient number, since it is larger than the sum of its proper divisors (1741819056121).

221211020111111 is a wasteful number, since it uses less digits than its factorization.

221211020111111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1741819056120.

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

Adding to 221211020111111 its reverse (111111020112122), we get a palindrome (332322040223233).

The spelling of 221211020111111 in words is "two hundred twenty-one trillion, two hundred eleven billion, twenty million, one hundred eleven thousand, one hundred eleven".