1265171849 has 2 divisors, whose sum is σ = 1265171850. Its totient is φ = 1265171848.

The previous prime is 1265171839. The next prime is 1265171899. The reversal of 1265171849 is 9481715621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1250117449 + 15054400 = 35357^2 + 3880^2 .

It is a cyclic number.

It is not a de Polignac number, because 1265171849 - 2¹⁶ = 1265106313 is a prime.

It is not a weakly prime, because it can be changed into another prime (1265171819) 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 as a sum of consecutive naturals, namely, 632585924 + 632585925.

It is an arithmetic number, because the mean of its divisors is an integer number (632585925).

Almost surely, 2^1265171849 is an apocalyptic number.

It is an amenable number.

1265171849 is a deficient number, since it is larger than the sum of its proper divisors (1).

1265171849 is an equidigital number, since it uses as much as digits as its factorization.

1265171849 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 120960, while the sum is 44.

The square root of 1265171849 is about 35569.2542654467. The cubic root of 1265171849 is about 1081.5580646735.

The spelling of 1265171849 in words is "one billion, two hundred sixty-five million, one hundred seventy-one thousand, eight hundred forty-nine".