221001212111 has 4 divisors (see below), whose sum is σ = 221017121952. Its totient is φ = 220985302272.

The previous prime is 221001212099. The next prime is 221001212141. The reversal of 221001212111 is 111212100122.

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

It is a cyclic number.

It is not a de Polignac number, because 221001212111 - 2³⁴ = 203821342927 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 (221001212141) 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, 7934066 + ... + 7961871.

It is an arithmetic number, because the mean of its divisors is an integer number (55254280488).

Almost surely, 2^221001212111 is an apocalyptic number.

221001212111 is a deficient number, since it is larger than the sum of its proper divisors (15909841).

221001212111 is a wasteful number, since it uses less digits than its factorization.

221001212111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15909840.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 221001212111 its reverse (111212100122), we get a palindrome (332213312233).

The spelling of 221001212111 in words is "two hundred twenty-one billion, one million, two hundred twelve thousand, one hundred eleven".