221900111 has 4 divisors (see below), whose sum is σ = 222050232. Its totient is φ = 221749992.

The previous prime is 221900053. The next prime is 221900117. The reversal of 221900111 is 111009122.

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-221900111 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 221900111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221900117) 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, 72821 + ... + 75806.

It is an arithmetic number, because the mean of its divisors is an integer number (55512558).

Almost surely, 2^221900111 is an apocalyptic number.

221900111 is a deficient number, since it is larger than the sum of its proper divisors (150121).

221900111 is a wasteful number, since it uses less digits than its factorization.

221900111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150120.

The product of its (nonzero) digits is 36, while the sum is 17.

The square root of 221900111 is about 14896.3119932418. The cubic root of 221900111 is about 605.4140652935.

Adding to 221900111 its reverse (111009122), we get a palindrome (332909233).

The spelling of 221900111 in words is "two hundred twenty-one million, nine hundred thousand, one hundred eleven".