6660091 has 2 divisors, whose sum is σ = 6660092. Its totient is φ = 6660090.

The previous prime is 6660061. The next prime is 6660103. The reversal of 6660091 is 1900666.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 6660091 - 2⁹ = 6659579 is a prime.

It is not a weakly prime, because it can be changed into another prime (6660011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3330045 + 3330046.

It is an arithmetic number, because the mean of its divisors is an integer number (3330046).

Almost surely, 2^6660091 is an apocalyptic number.

6660091 is a deficient number, since it is larger than the sum of its proper divisors (1).

6660091 is an equidigital number, since it uses as much as digits as its factorization.

6660091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 6660091 is about 2580.7152109444. The cubic root of 6660091 is about 188.1453060277.

The spelling of 6660091 in words is "six million, six hundred sixty thousand, ninety-one".