1340243243 has 4 divisors (see below), whose sum is σ = 1383476928. Its totient is φ = 1297009560.

The previous prime is 1340243239. The next prime is 1340243249. The reversal of 1340243243 is 3423420431.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1340243243 - 2² = 1340243239 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1340243249) 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 3 ways as a sum of consecutive naturals, for example, 21616796 + ... + 21616857.

It is an arithmetic number, because the mean of its divisors is an integer number (345869232).

Almost surely, 2^1340243243 is an apocalyptic number.

1340243243 is a deficient number, since it is larger than the sum of its proper divisors (43233685).

1340243243 is an equidigital number, since it uses as much as digits as its factorization.

1340243243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43233684.

The product of its (nonzero) digits is 6912, while the sum is 26.

The square root of 1340243243 is about 36609.3327308762. The cubic root of 1340243243 is about 1102.5404761270.

Adding to 1340243243 its reverse (3423420431), we get a palindrome (4763663674).

The spelling of 1340243243 in words is "one billion, three hundred forty million, two hundred forty-three thousand, two hundred forty-three".