1161273305 has 16 divisors (see below), whose sum is σ = 1432384464. Its totient is φ = 903156480.

The previous prime is 1161273277. The next prime is 1161273307. The reversal of 1161273305 is 5033721611.

It can be written as a sum of positive squares in 8 ways, for example, as 17007376 + 1144265929 = 4124^2 + 33827^2 .

It is not a de Polignac number, because 1161273305 - 2⁶ = 1161273241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1161273307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 342599 + ... + 345971.

It is an arithmetic number, because the mean of its divisors is an integer number (89524029).

Almost surely, 2^1161273305 is an apocalyptic number.

It is an amenable number.

1161273305 is a deficient number, since it is larger than the sum of its proper divisors (271111159).

1161273305 is a wasteful number, since it uses less digits than its factorization.

1161273305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5276.

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 1161273305 is about 34077.4603660543. The cubic root of 1161273305 is about 1051.1018833256.

Adding to 1161273305 its reverse (5033721611), we get a palindrome (6194994916).

The spelling of 1161273305 in words is "one billion, one hundred sixty-one million, two hundred seventy-three thousand, three hundred five".