1221048243 has 32 divisors (see below), whose sum is σ = 1965619200. Its totient is φ = 746301600.

The previous prime is 1221048233. The next prime is 1221048317. The reversal of 1221048243 is 3428401221.

It is not a de Polignac number, because 1221048243 - 2²⁰ = 1219999667 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (1221048233) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22488 + ... + 54293.

It is an arithmetic number, because the mean of its divisors is an integer number (61425600).

Almost surely, 2^1221048243 is an apocalyptic number.

1221048243 is a deficient number, since it is larger than the sum of its proper divisors (744570957).

1221048243 is a wasteful number, since it uses less digits than its factorization.

1221048243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76840 (or 76834 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 1221048243 is about 34943.5007261722. The cubic root of 1221048243 is about 1068.8356750031.

Adding to 1221048243 its reverse (3428401221), we get a palindrome (4649449464).

The spelling of 1221048243 in words is "one billion, two hundred twenty-one million, forty-eight thousand, two hundred forty-three".