1161281265 has 8 divisors (see below), whose sum is σ = 1858050048. Its totient is φ = 619350000.

The previous prime is 1161281243. The next prime is 1161281281. The reversal of 1161281265 is 5621821611.

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

It is a de Polignac number, because none of the positive numbers 2^k-1161281265 is a prime.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 38709361 + ... + 38709390.

It is an arithmetic number, because the mean of its divisors is an integer number (232256256).

Almost surely, 2^1161281265 is an apocalyptic number.

1161281265 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1161281265 is a deficient number, since it is larger than the sum of its proper divisors (696768783).

1161281265 is an equidigital number, since it uses as much as digits as its factorization.

1161281265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77418759.

The product of its digits is 5760, while the sum is 33.

The square root of 1161281265 is about 34077.5771585951. The cubic root of 1161281265 is about 1051.1042849285.

The spelling of 1161281265 in words is "one billion, one hundred sixty-one million, two hundred eighty-one thousand, two hundred sixty-five".