1220111 has 4 divisors (see below), whose sum is σ = 1225224. Its totient is φ = 1215000.

The previous prime is 1220099. The next prime is 1220147. The reversal of 1220111 is 1110221.

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-1220111 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 (1220171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2180 + ... + 2681.

It is an arithmetic number, because the mean of its divisors is an integer number (306306).

2^1220111 is an apocalyptic number.

1220111 is a deficient number, since it is larger than the sum of its proper divisors (5113).

1220111 is an equidigital number, since it uses as much as digits as its factorization.

1220111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5112.

The product of its (nonzero) digits is 4, while the sum is 8.

The square root of 1220111 is about 1104.5863479149. The cubic root of 1220111 is about 106.8562135396.

Adding to 1220111 its reverse (1110221), we get a palindrome (2330332).

It can be divided in two parts, 1220 and 111, that added together give a palindrome (1331).

The spelling of 1220111 in words is "one million, two hundred twenty thousand, one hundred eleven".