1211103221 has 4 divisors (see below), whose sum is σ = 1223094444. Its totient is φ = 1199112000.

The previous prime is 1211103209. The next prime is 1211103233. The reversal of 1211103221 is 1223011121.

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

It is an interprime number because it is at equal distance from previous prime (1211103209) and next prime (1211103233).

It can be written as a sum of positive squares in 2 ways, for example, as 825412900 + 385690321 = 28730^2 + 19639^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211103221 - 2¹⁴ = 1211086837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1211103196 and 1211103205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211103521) 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, 5995460 + ... + 5995661.

It is an arithmetic number, because the mean of its divisors is an integer number (305773611).

Almost surely, 2^1211103221 is an apocalyptic number.

It is an amenable number.

1211103221 is a deficient number, since it is larger than the sum of its proper divisors (11991223).

1211103221 is a wasteful number, since it uses less digits than its factorization.

1211103221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11991222.

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 1211103221 is about 34800.9083358466. The cubic root of 1211103221 is about 1065.9259936983.

Adding to 1211103221 its reverse (1223011121), we get a palindrome (2434114342).

The spelling of 1211103221 in words is "one billion, two hundred eleven million, one hundred three thousand, two hundred twenty-one".