666216001 has 8 divisors (see below), whose sum is σ = 727101504. Its totient is φ = 605383920.

The previous prime is 666215993. The next prime is 666216007. The reversal of 666216001 is 100612666.

666216001 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 666216001 - 2³ = 666215993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666216007) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15435 + ... + 39631.

It is an arithmetic number, because the mean of its divisors is an integer number (90887688).

Almost surely, 2^666216001 is an apocalyptic number.

It is an amenable number.

666216001 is a deficient number, since it is larger than the sum of its proper divisors (60885503).

666216001 is a wasteful number, since it uses less digits than its factorization.

666216001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26711.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 666216001 is about 25811.1603962317. The cubic root of 666216001 is about 873.3835740024.

Adding to 666216001 its reverse (100612666), we get a palindrome (766828667).

The spelling of 666216001 in words is "six hundred sixty-six million, two hundred sixteen thousand, one".