1213321331 has 4 divisors (see below), whose sum is σ = 1284693192. Its totient is φ = 1141949472.

The previous prime is 1213321303. The next prime is 1213321381. The reversal of 1213321331 is 1331233121.

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

It is a cyclic number.

It is not a de Polignac number, because 1213321331 - 2⁶ = 1213321267 is a prime.

It is a super-2 number, since 2×1213321331² = 2944297304519223122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1213321301) 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 3 ways as a sum of consecutive naturals, for example, 35685905 + ... + 35685938.

It is an arithmetic number, because the mean of its divisors is an integer number (321173298).

Almost surely, 2^1213321331 is an apocalyptic number.

1213321331 is a deficient number, since it is larger than the sum of its proper divisors (71371861).

1213321331 is an equidigital number, since it uses as much as digits as its factorization.

1213321331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71371860.

The product of its digits is 324, while the sum is 20.

The square root of 1213321331 is about 34832.7623222736. The cubic root of 1213321331 is about 1066.5763371533.

Adding to 1213321331 its reverse (1331233121), we get a palindrome (2544554452).

The spelling of 1213321331 in words is "one billion, two hundred thirteen million, three hundred twenty-one thousand, three hundred thirty-one".