1211331321 has 8 divisors (see below), whose sum is σ = 1794564960. Its totient is φ = 807554196.

The previous prime is 1211331287. The next prime is 1211331323. The reversal of 1211331321 is 1231331121.

1211331321 is a `hidden beast` number, since 1 + 2 + 11 + 331 + 321 = 666.

It is not a de Polignac number, because 1211331321 - 2³⁰ = 137589497 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1211331294 and 1211331303.

It is not an unprimeable number, because it can be changed into a prime (1211331323) 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, 22432035 + ... + 22432088.

It is an arithmetic number, because the mean of its divisors is an integer number (224320620).

Almost surely, 2^1211331321 is an apocalyptic number.

It is an amenable number.

1211331321 is a deficient number, since it is larger than the sum of its proper divisors (583233639).

1211331321 is an equidigital number, since it uses as much as digits as its factorization.

1211331321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44864132 (or 44864126 counting only the distinct ones).

The product of its digits is 108, while the sum is 18.

The square root of 1211331321 is about 34804.1853948631. The cubic root of 1211331321 is about 1065.9929085718.

Adding to 1211331321 its reverse (1231331121), we get a palindrome (2442662442).

It can be divided in two parts, 12113 and 31321, that added together give a palindrome (43434).

The spelling of 1211331321 in words is "one billion, two hundred eleven million, three hundred thirty-one thousand, three hundred twenty-one".