665601106 has 4 divisors (see below), whose sum is σ = 998401662. Its totient is φ = 332800552.

The previous prime is 665601067. The next prime is 665601107. The reversal of 665601106 is 601106566.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 542191225 + 123409881 = 23285^2 + 11109^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (665601107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 166400275 + ... + 166400278.

Almost surely, 2^665601106 is an apocalyptic number.

665601106 is a deficient number, since it is larger than the sum of its proper divisors (332800556).

665601106 is a wasteful number, since it uses less digits than its factorization.

665601106 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 332800555.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 665601106 is about 25799.2462292990. The cubic root of 665601106 is about 873.1147900546.

The spelling of 665601106 in words is "six hundred sixty-five million, six hundred one thousand, one hundred six".