665501001 has 8 divisors (see below), whose sum is σ = 968001504. Its totient is φ = 403333920.

The previous prime is 665500999. The next prime is 665501027. The reversal of 665501001 is 100105566.

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

It is not a de Polignac number, because 665501001 - 2¹ = 665500999 is a prime.

It is not an unprimeable number, because it can be changed into a prime (665501041) 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 7 ways as a sum of consecutive naturals, for example, 10083316 + ... + 10083381.

It is an arithmetic number, because the mean of its divisors is an integer number (121000188).

Almost surely, 2^665501001 is an apocalyptic number.

It is an amenable number.

665501001 is a deficient number, since it is larger than the sum of its proper divisors (302500503).

665501001 is a wasteful number, since it uses less digits than its factorization.

665501001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20166711.

The product of its (nonzero) digits is 900, while the sum is 24.

The square root of 665501001 is about 25797.3060802868. The cubic root of 665501001 is about 873.0710163202.

Adding to 665501001 its reverse (100105566), we get a palindrome (765606567).

The spelling of 665501001 in words is "six hundred sixty-five million, five hundred one thousand, one".