1161611065 has 4 divisors (see below), whose sum is σ = 1393933284. Its totient is φ = 929288848.

The previous prime is 1161611051. The next prime is 1161611089. The reversal of 1161611065 is 5601161611.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5601161611 = 6803 ⋅823337.

It can be written as a sum of positive squares in 2 ways, for example, as 346108816 + 815502249 = 18604^2 + 28557^2 .

It is a cyclic number.

It is not a de Polignac number, because 1161611065 - 2⁷ = 1161610937 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, 116161102 + ... + 116161111.

It is an arithmetic number, because the mean of its divisors is an integer number (348483321).

Almost surely, 2^1161611065 is an apocalyptic number.

It is an amenable number.

1161611065 is a deficient number, since it is larger than the sum of its proper divisors (232322219).

1161611065 is an equidigital number, since it uses as much as digits as its factorization.

1161611065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 232322218.

The product of its (nonzero) digits is 1080, while the sum is 28.

The square root of 1161611065 is about 34082.4157741202. The cubic root of 1161611065 is about 1051.2037788790.

Adding to 1161611065 its reverse (5601161611), we get a palindrome (6762772676).

The spelling of 1161611065 in words is "one billion, one hundred sixty-one million, six hundred eleven thousand, sixty-five".