1211221 has 8 divisors (see below), whose sum is σ = 1332000. Its totient is φ = 1092240.

The previous prime is 1211207. The next prime is 1211227. The reversal of 1211221 is 1221121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1211221 is a prime.

It is an Ulam number.

It is a Duffinian number.

1211221 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 1211198 and 1211207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1270 + ... + 2008.

It is an arithmetic number, because the mean of its divisors is an integer number (166500).

2^1211221 is an apocalyptic number.

1211221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1211221 is a deficient number, since it is larger than the sum of its proper divisors (120779).

1211221 is a wasteful number, since it uses less digits than its factorization.

1211221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 899.

The product of its digits is 8, while the sum is 10.

The square root of 1211221 is about 1100.5548600592. The cubic root of 1211221 is about 106.5960546115.

Adding to 1211221 its reverse (1221121), we get a palindrome (2432342).

It can be divided in two parts, 121 and 1221, that multiplied together give a palindrome (147741).

The spelling of 1211221 in words is "one million, two hundred eleven thousand, two hundred twenty-one".