1221326433 has 12 divisors (see below), whose sum is σ = 1768587028. Its totient is φ = 812164320.

The previous prime is 1221326429. The next prime is 1221326453. The reversal of 1221326433 is 3346231221.

1221326433 is a `hidden beast` number, since 1 + 2 + 2 + 13 + 2 + 643 + 3 = 666.

1221326433 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 477509904 + 743816529 = 21852^2 + 27273^2 .

It is not a de Polignac number, because 1221326433 - 2² = 1221326429 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221326397 and 1221326406.

It is not an unprimeable number, because it can be changed into a prime (1221326413) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 167338 + ... + 174483.

Almost surely, 2^1221326433 is an apocalyptic number.

It is an amenable number.

1221326433 is a deficient number, since it is larger than the sum of its proper divisors (547260595).

1221326433 is a wasteful number, since it uses less digits than its factorization.

1221326433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 342224 (or 342221 counting only the distinct ones).

The product of its digits is 5184, while the sum is 27.

The square root of 1221326433 is about 34947.4810680255. The cubic root of 1221326433 is about 1068.9168393688.

Adding to 1221326433 its reverse (3346231221), we get a palindrome (4567557654).

The spelling of 1221326433 in words is "one billion, two hundred twenty-one million, three hundred twenty-six thousand, four hundred thirty-three".