2660409 has 6 divisors (see below), whose sum is σ = 3842826. Its totient is φ = 1773600.

The previous prime is 2660401. The next prime is 2660417. The reversal of 2660409 is 9040662.

It is an interprime number because it is at equal distance from previous prime (2660401) and next prime (2660417).

It can be written as a sum of positive squares in only one way, i.e., 2471184 + 189225 = 1572^2 + 435^2 .

It is not a de Polignac number, because 2660409 - 2³ = 2660401 is a prime.

2660409 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2660401) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 147792 + ... + 147809.

It is an arithmetic number, because the mean of its divisors is an integer number (640471).

2^2660409 is an apocalyptic number.

It is an amenable number.

2660409 is a deficient number, since it is larger than the sum of its proper divisors (1182417).

2660409 is a wasteful number, since it uses less digits than its factorization.

2660409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295607 (or 295604 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 2660409 is about 1631.0760252054. The cubic root of 2660409 is about 138.5636993194.

The spelling of 2660409 in words is "two million, six hundred sixty thousand, four hundred nine".