6660190657 has 4 divisors (see below), whose sum is σ = 7051966596. Its totient is φ = 6268414720.

The previous prime is 6660190591. The next prime is 6660190679. The reversal of 6660190657 is 7560910666.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5819248656 + 840942001 = 76284^2 + 28999^2 .

It is a cyclic number.

It is not a de Polignac number, because 6660190657 - 2⁷ = 6660190529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6660190687) by changing a digit.

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

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 195887944 + ... + 195887977.

It is an arithmetic number, because the mean of its divisors is an integer number (1762991649).

Almost surely, 2^6660190657 is an apocalyptic number.

It is an amenable number.

6660190657 is a deficient number, since it is larger than the sum of its proper divisors (391775939).

6660190657 is a wasteful number, since it uses less digits than its factorization.

6660190657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 391775938.

The product of its (nonzero) digits is 408240, while the sum is 46.

The square root of 6660190657 is about 81609.9911591712. The cubic root of 6660190657 is about 1881.4624444844.

The spelling of 6660190657 in words is "six billion, six hundred sixty million, one hundred ninety thousand, six hundred fifty-seven".