6660278 has 4 divisors (see below), whose sum is σ = 9990420. Its totient is φ = 3330138.

The previous prime is 6660239. The next prime is 6660287. The reversal of 6660278 is 8720666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8720666 = 2 ⋅4360333.

It is a Curzon number.

It is a congruent 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 as a sum of consecutive naturals, namely, 1665068 + ... + 1665071.

It is an arithmetic number, because the mean of its divisors is an integer number (2497605).

Almost surely, 2^6660278 is an apocalyptic number.

6660278 is a deficient number, since it is larger than the sum of its proper divisors (3330142).

6660278 is a wasteful number, since it uses less digits than its factorization.

6660278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3330141.

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 6660278 is about 2580.7514409567. The cubic root of 6660278 is about 188.1470669067.

The spelling of 6660278 in words is "six million, six hundred sixty thousand, two hundred seventy-eight".