2665987 has 4 divisors (see below), whose sum is σ = 2669256. Its totient is φ = 2662720.

The previous prime is 2665973. The next prime is 2666021. The reversal of 2665987 is 7895662.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 7895662 = 2 ⋅3947831.

It is a cyclic number.

It is not a de Polignac number, because 2665987 - 2¹⁵ = 2633219 is a prime.

It is a Duffinian number.

2665987 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2665967) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 723 + ... + 2419.

It is an arithmetic number, because the mean of its divisors is an integer number (667314).

2^2665987 is an apocalyptic number.

2665987 is a deficient number, since it is larger than the sum of its proper divisors (3269).

2665987 is a wasteful number, since it uses less digits than its factorization.

2665987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3268.

The product of its digits is 181440, while the sum is 43.

The square root of 2665987 is about 1632.7850440275. The cubic root of 2665987 is about 138.6604725054.

The spelling of 2665987 in words is "two million, six hundred sixty-five thousand, nine hundred eighty-seven".