1321331331 has 4 divisors (see below), whose sum is σ = 1761775112. Its totient is φ = 880887552.

The previous prime is 1321331303. The next prime is 1321331339. The reversal of 1321331331 is 1331331231.

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

It is not a de Polignac number, because 1321331331 - 2¹³ = 1321323139 is a prime.

It is a super-2 number, since 2×1321331331² = 3491832972564463122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1321331298 and 1321331307.

It is not an unprimeable number, because it can be changed into a prime (1321331339) 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, 220221886 + ... + 220221891.

It is an arithmetic number, because the mean of its divisors is an integer number (440443778).

Almost surely, 2^1321331331 is an apocalyptic number.

1321331331 is a deficient number, since it is larger than the sum of its proper divisors (440443781).

1321331331 is an equidigital number, since it uses as much as digits as its factorization.

1321331331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 440443780.

The product of its digits is 486, while the sum is 21.

The square root of 1321331331 is about 36350.1214715990. The cubic root of 1321331331 is about 1097.3299791452.

Adding to 1321331331 its reverse (1331331231), we get a palindrome (2652662562).

It can be divided in two parts, 13213 and 31331, that added together give a palindrome (44544).

The spelling of 1321331331 in words is "one billion, three hundred twenty-one million, three hundred thirty-one thousand, three hundred thirty-one".