1111221 has 24 divisors (see below), whose sum is σ = 1707264. Its totient is φ = 695520.

The previous prime is 1111219. The next prime is 1111247. The reversal of 1111221 is 1221111.

It is a happy number.

It is not a de Polignac number, because 1111221 - 2¹ = 1111219 is a prime.

It is a super-2 number, since 2×1111221² = 2469624221682, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

1111221 is a modest number, since divided by 1221 gives 111 as remainder.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1111211) 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 23 ways as a sum of consecutive naturals, for example, 15616 + ... + 15686.

It is an arithmetic number, because the mean of its divisors is an integer number (71136).

2^1111221 is an apocalyptic number.

It is an amenable number.

1111221 is a deficient number, since it is larger than the sum of its proper divisors (596043).

1111221 is a wasteful number, since it uses less digits than its factorization.

1111221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161 (or 158 counting only the distinct ones).

The product of its digits is 4, while the sum is 9.

The square root of 1111221 is about 1054.1446769775. The cubic root of 1111221 is about 103.5778312558.

Adding to 1111221 its reverse (1221111), we get a palindrome (2332332).

It can be divided in two parts, 111 and 1221, that multiplied together give a palindrome (135531).

The spelling of 1111221 in words is "one million, one hundred eleven thousand, two hundred twenty-one".