665965079 has 4 divisors (see below), whose sum is σ = 717193176. Its totient is φ = 614736984.

The previous prime is 665965063. The next prime is 665965127. The reversal of 665965079 is 970569566.

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

It is a cyclic number.

It is not a de Polignac number, because 665965079 - 2⁴ = 665965063 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 665965079.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665665079) 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, 25614029 + ... + 25614054.

It is an arithmetic number, because the mean of its divisors is an integer number (179298294).

Almost surely, 2^665965079 is an apocalyptic number.

665965079 is a deficient number, since it is larger than the sum of its proper divisors (51228097).

665965079 is a wasteful number, since it uses less digits than its factorization.

665965079 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51228096.

The product of its (nonzero) digits is 3061800, while the sum is 53.

The square root of 665965079 is about 25806.2992116266. The cubic root of 665965079 is about 873.2739105339.

The spelling of 665965079 in words is "six hundred sixty-five million, nine hundred sixty-five thousand, seventy-nine".