1323121221 has 24 divisors (see below), whose sum is σ = 2066145120. Its totient is φ = 813066336.

The previous prime is 1323121213. The next prime is 1323121229. The reversal of 1323121221 is 1221213231.

1323121221 is a `hidden beast` number, since 1 + 323 + 121 + 221 = 666.

It is an interprime number because it is at equal distance from previous prime (1323121213) and next prime (1323121229).

It is not a de Polignac number, because 1323121221 - 2³ = 1323121213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1323121194 and 1323121203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1323121229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 98235 + ... + 110888.

It is an arithmetic number, because the mean of its divisors is an integer number (86089380).

Almost surely, 2^1323121221 is an apocalyptic number.

It is an amenable number.

1323121221 is a deficient number, since it is larger than the sum of its proper divisors (743023899).

1323121221 is a wasteful number, since it uses less digits than its factorization.

1323121221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 209185 (or 209182 counting only the distinct ones).

The product of its digits is 144, while the sum is 18.

The square root of 1323121221 is about 36374.7332773726. The cubic root of 1323121221 is about 1097.8252406826.

Adding to 1323121221 its reverse (1221213231), we get a palindrome (2544334452).

The spelling of 1323121221 in words is "one billion, three hundred twenty-three million, one hundred twenty-one thousand, two hundred twenty-one".