1221323331 has 16 divisors (see below), whose sum is σ = 1653516800. Its totient is φ = 801728928.

The previous prime is 1221323329. The next prime is 1221323347. The reversal of 1221323331 is 1333231221.

It is not a de Polignac number, because 1221323331 - 2¹ = 1221323329 is a prime.

It is a super-2 number, since 2×1221323331² = 2983261357689871122, 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 = 1221323298 and 1221323307.

It is not an unprimeable number, because it can be changed into a prime (1221323431) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 83025 + ... + 96621.

It is an arithmetic number, because the mean of its divisors is an integer number (103344800).

Almost surely, 2^1221323331 is an apocalyptic number.

1221323331 is a deficient number, since it is larger than the sum of its proper divisors (432193469).

1221323331 is a wasteful number, since it uses less digits than its factorization.

1221323331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14058.

The product of its digits is 648, while the sum is 21.

The square root of 1221323331 is about 34947.4366871163. The cubic root of 1221323331 is about 1068.9159344012.

Adding to 1221323331 its reverse (1333231221), we get a palindrome (2554554552).

The spelling of 1221323331 in words is "one billion, two hundred twenty-one million, three hundred twenty-three thousand, three hundred thirty-one".