11565516109 has 12 divisors (see below), whose sum is σ = 14245162524. Its totient is φ = 9330163584.

The previous prime is 11565516101. The next prime is 11565516133. The reversal of 11565516109 is 90161556511.

It can be written as a sum of positive squares in 2 ways, for example, as 5469342025 + 6096174084 = 73955^2 + 78078^2 .

It is not a de Polignac number, because 11565516109 - 2³ = 11565516101 is a prime.

It is a super-2 number, since 2×11565516109² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11565516101) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6941254 + ... + 6942919.

It is an arithmetic number, because the mean of its divisors is an integer number (1187096877).

Almost surely, 2^11565516109 is an apocalyptic number.

It is an amenable number.

11565516109 is a deficient number, since it is larger than the sum of its proper divisors (2679646415).

11565516109 is a wasteful number, since it uses less digits than its factorization.

11565516109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13884204 (or 13884197 counting only the distinct ones).

The product of its (nonzero) digits is 40500, while the sum is 40.

The spelling of 11565516109 in words is "eleven billion, five hundred sixty-five million, five hundred sixteen thousand, one hundred nine".