666546517 has 16 divisors (see below), whose sum is σ = 821705472. Its totient is φ = 526515840.

The previous prime is 666546499. The next prime is 666546521. The reversal of 666546517 is 715645666.

It is a cyclic number.

It is not a de Polignac number, because 666546517 - 2¹¹ = 666544469 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666546917) 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 15 ways as a sum of consecutive naturals, for example, 53217 + ... + 64537.

It is an arithmetic number, because the mean of its divisors is an integer number (51356592).

Almost surely, 2^666546517 is an apocalyptic number.

It is an amenable number.

666546517 is a deficient number, since it is larger than the sum of its proper divisors (155158955).

666546517 is a wasteful number, since it uses less digits than its factorization.

666546517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11988.

The product of its digits is 907200, while the sum is 46.

The square root of 666546517 is about 25817.5621815848. The cubic root of 666546517 is about 873.5279813824.

The spelling of 666546517 in words is "six hundred sixty-six million, five hundred forty-six thousand, five hundred seventeen".