665101567 has 4 divisors (see below), whose sum is σ = 716263240. Its totient is φ = 613939896.

The previous prime is 665101561. The next prime is 665101571. The reversal of 665101567 is 765101566.

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 665101567 - 2²⁷ = 530883839 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665101561) 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, 25580817 + ... + 25580842.

It is an arithmetic number, because the mean of its divisors is an integer number (179065810).

Almost surely, 2^665101567 is an apocalyptic number.

665101567 is a deficient number, since it is larger than the sum of its proper divisors (51161673).

665101567 is a wasteful number, since it uses less digits than its factorization.

665101567 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51161672.

The product of its (nonzero) digits is 37800, while the sum is 37.

The square root of 665101567 is about 25789.5631409297. The cubic root of 665101567 is about 872.8963088235.

Subtracting 665101567 from its reverse (765101566), we obtain a palindrome (99999999).

The spelling of 665101567 in words is "six hundred sixty-five million, one hundred one thousand, five hundred sixty-seven".