1189378265 has 4 divisors (see below), whose sum is σ = 1427253924. Its totient is φ = 951502608.

The previous prime is 1189378181. The next prime is 1189378291. The reversal of 1189378265 is 5628739811.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5628739811 = 37 ⋅152128103.

It can be written as a sum of positive squares in 2 ways, for example, as 946423696 + 242954569 = 30764^2 + 15587^2 .

It is a cyclic number.

It is not a de Polignac number, because 1189378265 - 2¹² = 1189374169 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 118937822 + ... + 118937831.

It is an arithmetic number, because the mean of its divisors is an integer number (356813481).

Almost surely, 2^1189378265 is an apocalyptic number.

It is an amenable number.

1189378265 is a deficient number, since it is larger than the sum of its proper divisors (237875659).

1189378265 is an equidigital number, since it uses as much as digits as its factorization.

1189378265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237875658.

The product of its digits is 725760, while the sum is 50.

The square root of 1189378265 is about 34487.3638453275. The cubic root of 1189378265 is about 1059.5139176923.

The spelling of 1189378265 in words is "one billion, one hundred eighty-nine million, three hundred seventy-eight thousand, two hundred sixty-five".