2609666 has 4 divisors (see below), whose sum is σ = 3914502. Its totient is φ = 1304832.

The previous prime is 2609657. The next prime is 2609671. The reversal of 2609666 is 6669062.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 6669062 = 2 ⋅3334531.

It can be written as a sum of positive squares in only one way, i.e., 1651225 + 958441 = 1285^2 + 979^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 652415 + ... + 652418.

2^2609666 is an apocalyptic number.

2609666 is a deficient number, since it is larger than the sum of its proper divisors (1304836).

2609666 is a wasteful number, since it uses less digits than its factorization.

2609666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1304835.

The product of its (nonzero) digits is 23328, while the sum is 35.

The square root of 2609666 is about 1615.4460684282. The cubic root of 2609666 is about 137.6770787391.

It can be divided in two parts, 26096 and 66, that added together give a palindrome (26162).

The spelling of 2609666 in words is "two million, six hundred nine thousand, six hundred sixty-six".