2665312785 has 48 divisors (see below), whose sum is σ = 4918914000. Its totient is φ = 1330421760.

The previous prime is 2665312777. The next prime is 2665312873. The reversal of 2665312785 is 5872135662.

2665312785 is a `hidden beast` number, since 266 + 5 + 312 + 78 + 5 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 28387584 + 2636925201 = 5328^2 + 51351^2 .

It is not a de Polignac number, because 2665312785 - 2³ = 2665312777 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 2665312785.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 128841 + ... + 148089.

It is an arithmetic number, because the mean of its divisors is an integer number (102477375).

Almost surely, 2^2665312785 is an apocalyptic number.

It is an amenable number.

2665312785 is a deficient number, since it is larger than the sum of its proper divisors (2253601215).

2665312785 is a wasteful number, since it uses less digits than its factorization.

2665312785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19458 (or 19455 counting only the distinct ones).

The product of its digits is 604800, while the sum is 45.

The square root of 2665312785 is about 51626.6673822744. The cubic root of 2665312785 is about 1386.4878266941.

The spelling of 2665312785 in words is "two billion, six hundred sixty-five million, three hundred twelve thousand, seven hundred eighty-five".