1211331121 has 64 divisors (see below), whose sum is σ = 1674441216. Its totient is φ = 853079040.

The previous prime is 1211331119. The next prime is 1211331151.

It is a happy number.

1211331121 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1211331121 - 2¹ = 1211331119 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1211331095 and 1211331104.

It is not an unprimeable number, because it can be changed into a prime (1211331151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8841765 + ... + 8841901.

It is an arithmetic number, because the mean of its divisors is an integer number (26163144).

Almost surely, 2^1211331121 is an apocalyptic number.

1211331121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1211331121 is a deficient number, since it is larger than the sum of its proper divisors (463110095).

1211331121 is a wasteful number, since it uses less digits than its factorization.

1211331121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 263 (or 241 counting only the distinct ones).

The product of its digits is 36, while the sum is 16.

The square root of 1211331121 is about 34804.1825216453. The cubic root of 1211331121 is about 1065.9928499040.

It can be divided in two parts, 12113 and 31121, that added together give a palindrome (43234).

The spelling of 1211331121 in words is "one billion, two hundred eleven million, three hundred thirty-one thousand, one hundred twenty-one".