1221243243 has 8 divisors (see below), whose sum is σ = 1776353856. Its totient is φ = 740147400.

The previous prime is 1221243223. The next prime is 1221243269. The reversal of 1221243243 is 3423421221.

It is a happy number.

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

It is not a de Polignac number, because 1221243243 - 2⁵ = 1221243211 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221243223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18503653 + ... + 18503718.

It is an arithmetic number, because the mean of its divisors is an integer number (222044232).

Almost surely, 2^1221243243 is an apocalyptic number.

1221243243 is a deficient number, since it is larger than the sum of its proper divisors (555110613).

1221243243 is a wasteful number, since it uses less digits than its factorization.

1221243243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37007385.

The product of its digits is 2304, while the sum is 24.

The square root of 1221243243 is about 34946.2908332201. The cubic root of 1221243243 is about 1068.8925692506.

Adding to 1221243243 its reverse (3423421221), we get a palindrome (4644664464).

It can be divided in two parts, 12212 and 43243, that added together give a palindrome (55455).

The spelling of 1221243243 in words is "one billion, two hundred twenty-one million, two hundred forty-three thousand, two hundred forty-three".