1221535244 has 12 divisors (see below), whose sum is σ = 2230629744. Its totient is φ = 584212464.

The previous prime is 1221535243. The next prime is 1221535247. The reversal of 1221535244 is 4425351221.

It is not an unprimeable number, because it can be changed into a prime (1221535241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6638687 + ... + 6638870.

It is an arithmetic number, because the mean of its divisors is an integer number (185885812).

Almost surely, 2^1221535244 is an apocalyptic number.

It is an amenable number.

1221535244 is a deficient number, since it is larger than the sum of its proper divisors (1009094500).

1221535244 is a wasteful number, since it uses less digits than its factorization.

1221535244 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13277584 (or 13277582 counting only the distinct ones).

The product of its digits is 9600, while the sum is 29.

The square root of 1221535244 is about 34950.4684374902. The cubic root of 1221535244 is about 1068.9777537073.

Adding to 1221535244 its reverse (4425351221), we get a palindrome (5646886465).

The spelling of 1221535244 in words is "one billion, two hundred twenty-one million, five hundred thirty-five thousand, two hundred forty-four".