1265434243 has 4 divisors (see below), whose sum is σ = 1265505480. Its totient is φ = 1265363008.

The previous prime is 1265434237. The next prime is 1265434259. The reversal of 1265434243 is 3424345621.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 1265434243 - 2²¹ = 1263337091 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1265434199 and 1265434208.

It is not an unprimeable number, because it can be changed into a prime (1265434283) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15123 + ... + 52531.

It is an arithmetic number, because the mean of its divisors is an integer number (316376370).

Almost surely, 2^1265434243 is an apocalyptic number.

1265434243 is a deficient number, since it is larger than the sum of its proper divisors (71237).

1265434243 is an equidigital number, since it uses as much as digits as its factorization.

1265434243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71236.

The product of its digits is 69120, while the sum is 34.

The square root of 1265434243 is about 35572.9425687558. The cubic root of 1265434243 is about 1081.6328304664.

Adding to 1265434243 its reverse (3424345621), we get a palindrome (4689779864).

The spelling of 1265434243 in words is "one billion, two hundred sixty-five million, four hundred thirty-four thousand, two hundred forty-three".