42809666 has 8 divisors (see below), whose sum is σ = 65950140. Its totient is φ = 20826288.

The previous prime is 42809653. The next prime is 42809671. The reversal of 42809666 is 66690824.

It can be written as a sum of positive squares in 2 ways, for example, as 42523441 + 286225 = 6521^2 + 535^2 .

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

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 289181 + ... + 289328.

Almost surely, 2^42809666 is an apocalyptic number.

42809666 is a deficient number, since it is larger than the sum of its proper divisors (23140474).

42809666 is a wasteful number, since it uses less digits than its factorization.

42809666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 578548.

The product of its (nonzero) digits is 124416, while the sum is 41.

The square root of 42809666 is about 6542.9095974192. The cubic root of 42809666 is about 349.8221300300.

The spelling of 42809666 in words is "forty-two million, eight hundred nine thousand, six hundred sixty-six".