666545201 has 4 divisors (see below), whose sum is σ = 761765952. Its totient is φ = 571324452.

The previous prime is 666545189. The next prime is 666545237. The reversal of 666545201 is 102545666.

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 666545201 - 2¹⁴ = 666528817 is a prime.

It is a super-2 number, since 2×666545201² = 888565009952260802, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (666545101) 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, 47610365 + ... + 47610378.

It is an arithmetic number, because the mean of its divisors is an integer number (190441488).

Almost surely, 2^666545201 is an apocalyptic number.

It is an amenable number.

666545201 is a deficient number, since it is larger than the sum of its proper divisors (95220751).

666545201 is an equidigital number, since it uses as much as digits as its factorization.

666545201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95220750.

The product of its (nonzero) digits is 43200, while the sum is 35.

The square root of 666545201 is about 25817.5366950451. The cubic root of 666545201 is about 873.5274064970.

The spelling of 666545201 in words is "six hundred sixty-six million, five hundred forty-five thousand, two hundred one".