1265378259 has 8 divisors (see below), whose sum is σ = 1710934272. Its totient is φ = 831703880.

The previous prime is 1265378249. The next prime is 1265378267. The reversal of 1265378259 is 9528735621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1265378259 - 2⁸ = 1265378003 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1265378239) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2970159 + ... + 2970584.

It is an arithmetic number, because the mean of its divisors is an integer number (213866784).

Almost surely, 2^1265378259 is an apocalyptic number.

1265378259 is a deficient number, since it is larger than the sum of its proper divisors (445556013).

1265378259 is an equidigital number, since it uses as much as digits as its factorization.

1265378259 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5940817.

The product of its digits is 907200, while the sum is 48.

The square root of 1265378259 is about 35572.1556698494. The cubic root of 1265378259 is about 1081.6168794136.

The spelling of 1265378259 in words is "one billion, two hundred sixty-five million, three hundred seventy-eight thousand, two hundred fifty-nine".