66101565 has 16 divisors (see below), whose sum is σ = 105872256. Its totient is φ = 35217600.

The previous prime is 66101561. The next prime is 66101617. The reversal of 66101565 is 56510166.

It is not a de Polignac number, because 66101565 - 2² = 66101561 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66101561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19120 + ... + 22310.

It is an arithmetic number, because the mean of its divisors is an integer number (6617016).

Almost surely, 2^66101565 is an apocalyptic number.

It is an amenable number.

66101565 is a deficient number, since it is larger than the sum of its proper divisors (39770691).

66101565 is a wasteful number, since it uses less digits than its factorization.

66101565 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4580.

The product of its (nonzero) digits is 5400, while the sum is 30.

The square root of 66101565 is about 8130.2868953070. The cubic root of 66101565 is about 404.3311930628.

It can be divided in two parts, 66101 and 565, that added together give a palindrome (66666).

The spelling of 66101565 in words is "sixty-six million, one hundred one thousand, five hundred sixty-five".