665766061 has 4 divisors (see below), whose sum is σ = 700806400. Its totient is φ = 630725724.

The previous prime is 665766029. The next prime is 665766071. The reversal of 665766061 is 160667566.

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 665766061 - 2⁵ = 665766029 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 665765999 and 665766017.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665766071) 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 3 ways as a sum of consecutive naturals, for example, 17520141 + ... + 17520178.

It is an arithmetic number, because the mean of its divisors is an integer number (175201600).

Almost surely, 2^665766061 is an apocalyptic number.

It is an amenable number.

665766061 is a deficient number, since it is larger than the sum of its proper divisors (35040339).

665766061 is a wasteful number, since it uses less digits than its factorization.

665766061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35040338.

The product of its (nonzero) digits is 272160, while the sum is 43.

The square root of 665766061 is about 25802.4429269788. The cubic root of 665766061 is about 873.1869117066.

The spelling of 665766061 in words is "six hundred sixty-five million, seven hundred sixty-six thousand, sixty-one".