1221033042243 has 80 divisors (see below), whose sum is σ = 2245388783616. Its totient is φ = 645867794880.

The previous prime is 1221033042209. The next prime is 1221033042253. The reversal of 1221033042243 is 3422403301221.

1221033042243 is a `hidden beast` number, since 12 + 2 + 103 + 304 + 2 + 243 = 666.

It is not a de Polignac number, because 1221033042243 - 2²¹ = 1221030945091 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 (1221033042253) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 1105896 + ... + 1914437.

Almost surely, 2^{1221033042243} is an apocalyptic number.

1221033042243 is a deficient number, since it is larger than the sum of its proper divisors (1024355741373).

1221033042243 is a wasteful number, since it uses less digits than its factorization.

1221033042243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3020406 (or 3020397 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

Adding to 1221033042243 its reverse (3422403301221), we get a palindrome (4643436343464).

The spelling of 1221033042243 in words is "one trillion, two hundred twenty-one billion, thirty-three million, forty-two thousand, two hundred forty-three".