1153440243 has 20 divisors (see below), whose sum is σ = 1723979928. Its totient is φ = 768540960.

The previous prime is 1153440241. The next prime is 1153440269. The reversal of 1153440243 is 3420443511.

It is a happy number.

It is not a de Polignac number, because 1153440243 - 2¹ = 1153440241 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 (1153440241) 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 19 ways as a sum of consecutive naturals, for example, 238255 + ... + 243047.

Almost surely, 2^1153440243 is an apocalyptic number.

1153440243 is a deficient number, since it is larger than the sum of its proper divisors (570539685).

1153440243 is an equidigital number, since it uses as much as digits as its factorization.

1153440243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7776 (or 7767 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 1153440243 is about 33962.3356528964. The cubic root of 1153440243 is about 1048.7332396933.

Adding to 1153440243 its reverse (3420443511), we get a palindrome (4573883754).

The spelling of 1153440243 in words is "one billion, one hundred fifty-three million, four hundred forty thousand, two hundred forty-three".