665808745 has 8 divisors (see below), whose sum is σ = 913109184. Its totient is φ = 456554544.

The previous prime is 665808739. The next prime is 665808763. The reversal of 665808745 is 547808566.

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 665808745 - 2⁵ = 665808713 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9511519 + ... + 9511588.

It is an arithmetic number, because the mean of its divisors is an integer number (114138648).

Almost surely, 2^665808745 is an apocalyptic number.

It is an amenable number.

665808745 is a deficient number, since it is larger than the sum of its proper divisors (247300439).

665808745 is a wasteful number, since it uses less digits than its factorization.

665808745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19023119.

The product of its (nonzero) digits is 1612800, while the sum is 49.

The square root of 665808745 is about 25803.2700447056. The cubic root of 665808745 is about 873.2055720719.

The spelling of 665808745 in words is "six hundred sixty-five million, eight hundred eight thousand, seven hundred forty-five".