6611615666065 has 4 divisors (see below), whose sum is σ = 7933938799284. Its totient is φ = 5289292532848.

The previous prime is 6611615666011. The next prime is 6611615666069. The reversal of 6611615666065 is 5606665161166.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4790565277696 + 1821050388369 = 2188736^2 + 1349463^2 .

It is a cyclic number.

It is not a de Polignac number, because 6611615666065 - 2³³ = 6603025731473 is a prime.

It is a super-2 number, since 2×6611615666065² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 6611615665997 and 6611615666015.

It is not an unprimeable number, because it can be changed into a prime (6611615666069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 661161566602 + ... + 661161566611.

It is an arithmetic number, because the mean of its divisors is an integer number (1983484699821).

Almost surely, 2^{6611615666065} is an apocalyptic number.

It is an amenable number.

6611615666065 is a deficient number, since it is larger than the sum of its proper divisors (1322323133219).

6611615666065 is a wasteful number, since it uses less digits than its factorization.

6611615666065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1322323133218.

The product of its (nonzero) digits is 6998400, while the sum is 55.

The spelling of 6611615666065 in words is "six trillion, six hundred eleven billion, six hundred fifteen million, six hundred sixty-six thousand, sixty-five".