1221144443 has 8 divisors (see below), whose sum is σ = 1227187200. Its totient is φ = 1215117288.

The previous prime is 1221144371. The next prime is 1221144461. The reversal of 1221144443 is 3444411221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221144443 - 2²² = 1216950139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221144473) 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 7 ways as a sum of consecutive naturals, for example, 171998 + ... + 178956.

It is an arithmetic number, because the mean of its divisors is an integer number (153398400).

Almost surely, 2^1221144443 is an apocalyptic number.

1221144443 is a deficient number, since it is larger than the sum of its proper divisors (6042757).

1221144443 is an equidigital number, since it uses as much as digits as its factorization.

1221144443 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7801.

The product of its digits is 3072, while the sum is 26.

The square root of 1221144443 is about 34944.8772068239. The cubic root of 1221144443 is about 1068.8637435888.

Adding to 1221144443 its reverse (3444411221), we get a palindrome (4665555664).

The spelling of 1221144443 in words is "one billion, two hundred twenty-one million, one hundred forty-four thousand, four hundred forty-three".