665632001 has 4 divisors (see below), whose sum is σ = 679794432. Its totient is φ = 651469572.

The previous prime is 665631977. The next prime is 665632003. The reversal of 665632001 is 100236566.

665632001 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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, and also an emirpimes, since its reverse is a distinct semiprime: 100236566 = 2 ⋅50118283.

It is a cyclic number.

It is not a de Polignac number, because 665632001 - 2²² = 661437697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (665632003) 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, 7081145 + ... + 7081238.

It is an arithmetic number, because the mean of its divisors is an integer number (169948608).

Almost surely, 2^665632001 is an apocalyptic number.

It is an amenable number.

665632001 is a deficient number, since it is larger than the sum of its proper divisors (14162431).

665632001 is a wasteful number, since it uses less digits than its factorization.

665632001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14162430.

The product of its (nonzero) digits is 6480, while the sum is 29.

The square root of 665632001 is about 25799.8449801544. The cubic root of 665632001 is about 873.1282988783.

Adding to 665632001 its reverse (100236566), we get a palindrome (765868567).

The spelling of 665632001 in words is "six hundred sixty-five million, six hundred thirty-two thousand, one".