2666520165 has 16 divisors (see below), whose sum is σ = 4267080576. Its totient is φ = 1421928000.

The previous prime is 2666520161. The next prime is 2666520179. The reversal of 2666520165 is 5610256662.

It is a happy number.

It is not a de Polignac number, because 2666520165 - 2² = 2666520161 is a prime.

It is a super-2 number, since 2×2666520165² = 14220659580703254450, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2666520161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 162435 + ... + 178095.

It is an arithmetic number, because the mean of its divisors is an integer number (266692536).

Almost surely, 2^2666520165 is an apocalyptic number.

It is an amenable number.

2666520165 is a deficient number, since it is larger than the sum of its proper divisors (1600560411).

2666520165 is a wasteful number, since it uses less digits than its factorization.

2666520165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27020.

The product of its (nonzero) digits is 129600, while the sum is 39.

The square root of 2666520165 is about 51638.3594336613. The cubic root of 2666520165 is about 1386.6971535906.

The spelling of 2666520165 in words is "two billion, six hundred sixty-six million, five hundred twenty thousand, one hundred sixty-five".