166665565 has 8 divisors (see below), whose sum is σ = 218180448. Its totient is φ = 121211280.

The previous prime is 166665563. The next prime is 166665593. The reversal of 166665565 is 565566661.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 166665565 - 2¹ = 166665563 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 (166665563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1515087 + ... + 1515196.

It is an arithmetic number, because the mean of its divisors is an integer number (27272556).

Almost surely, 2^166665565 is an apocalyptic number.

It is an amenable number.

166665565 is a deficient number, since it is larger than the sum of its proper divisors (51514883).

166665565 is a wasteful number, since it uses less digits than its factorization.

166665565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3030299.

The product of its digits is 972000, while the sum is 46.

The square root of 166665565 is about 12909.9018199210. The cubic root of 166665565 is about 550.3199956054.

The spelling of 166665565 in words is "one hundred sixty-six million, six hundred sixty-five thousand, five hundred sixty-five".