2666665 has 8 divisors (see below), whose sum is σ = 3214728. Its totient is φ = 2123520.

The previous prime is 2666663. The next prime is 2666683. The reversal of 2666665 is 5666662.

It can be written as a sum of positive squares in 4 ways, for example, as 1382976 + 1283689 = 1176^2 + 1133^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2666665 - 2¹ = 2666663 is a prime.

It is a super-2 number, since 2×2666665² = 14222204444450, which 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 (2666663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 99 + ... + 2311.

It is an arithmetic number, because the mean of its divisors is an integer number (401841).

2^2666665 is an apocalyptic number.

It is an amenable number.

2666665 is a deficient number, since it is larger than the sum of its proper divisors (548063).

2666665 is a wasteful number, since it uses less digits than its factorization.

2666665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2459.

The product of its digits is 77760, while the sum is 37.

The square root of 2666665 is about 1632.9926515450. The cubic root of 2666665 is about 138.6722259801.

The spelling of 2666665 in words is "two million, six hundred sixty-six thousand, six hundred sixty-five".