1221322133 has 4 divisors (see below), whose sum is σ = 1221393888. Its totient is φ = 1221250380.

The previous prime is 1221322127. The next prime is 1221322231. The reversal of 1221322133 is 3312231221.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1221322133 - 2⁴ = 1221322117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221322633) 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, 5768 + ... + 49758.

It is an arithmetic number, because the mean of its divisors is an integer number (305348472).

Almost surely, 2^1221322133 is an apocalyptic number.

It is an amenable number.

1221322133 is a deficient number, since it is larger than the sum of its proper divisors (71755).

1221322133 is an equidigital number, since it uses as much as digits as its factorization.

1221322133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71754.

The product of its digits is 432, while the sum is 20.

The square root of 1221322133 is about 34947.4195470853. The cubic root of 1221322133 is about 1068.9155849000.

Adding to 1221322133 its reverse (3312231221), we get a palindrome (4533553354).

The spelling of 1221322133 in words is "one billion, two hundred twenty-one million, three hundred twenty-two thousand, one hundred thirty-three".