6660457691 has 8 divisors (see below), whose sum is σ = 7063979424. Its totient is φ = 6266430720.

The previous prime is 6660457681. The next prime is 6660457697. The reversal of 6660457691 is 1967540666.

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

It is a cyclic number.

It is not a de Polignac number, because 6660457691 - 2⁶ = 6660457627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6660457697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2372246 + ... + 2375051.

It is an arithmetic number, because the mean of its divisors is an integer number (882997428).

Almost surely, 2^6660457691 is an apocalyptic number.

6660457691 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

6660457691 is a deficient number, since it is larger than the sum of its proper divisors (403521733).

6660457691 is a wasteful number, since it uses less digits than its factorization.

6660457691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4747381.

The product of its (nonzero) digits is 1632960, while the sum is 50.

The square root of 6660457691 is about 81611.6271802002. The cubic root of 6660457691 is about 1881.4875892965.

The spelling of 6660457691 in words is "six billion, six hundred sixty million, four hundred fifty-seven thousand, six hundred ninety-one".