1265285291 has 4 divisors (see below), whose sum is σ = 1266812400. Its totient is φ = 1263758184.

The previous prime is 1265285279. The next prime is 1265285293. The reversal of 1265285291 is 1925825621.

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 1265285291 - 2¹⁸ = 1265023147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1265285293) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 762311 + ... + 763968.

It is an arithmetic number, because the mean of its divisors is an integer number (316703100).

Almost surely, 2^1265285291 is an apocalyptic number.

1265285291 is a deficient number, since it is larger than the sum of its proper divisors (1527109).

1265285291 is an equidigital number, since it uses as much as digits as its factorization.

1265285291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1527108.

The product of its digits is 86400, while the sum is 41.

The square root of 1265285291 is about 35570.8488934408. The cubic root of 1265285291 is about 1081.5903897796.

The spelling of 1265285291 in words is "one billion, two hundred sixty-five million, two hundred eighty-five thousand, two hundred ninety-one".