666564001 has 4 divisors (see below), whose sum is σ = 675001600. Its totient is φ = 658126404.

The previous prime is 666563971. The next prime is 666564007. The reversal of 666564001 is 100465666.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 666564001 - 2¹³ = 666555809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666564007) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4218681 + ... + 4218838.

It is an arithmetic number, because the mean of its divisors is an integer number (168750400).

Almost surely, 2^666564001 is an apocalyptic number.

It is an amenable number.

666564001 is a deficient number, since it is larger than the sum of its proper divisors (8437599).

666564001 is an equidigital number, since it uses as much as digits as its factorization.

666564001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8437598.

The product of its (nonzero) digits is 25920, while the sum is 34.

The square root of 666564001 is about 25817.9007860825. The cubic root of 666564001 is about 873.5356190738.

The spelling of 666564001 in words is "six hundred sixty-six million, five hundred sixty-four thousand, one".