65581820165 has 32 divisors (see below), whose sum is σ = 79841728512. Its totient is φ = 51710400000.

The previous prime is 65581820153. The next prime is 65581820167. The reversal of 65581820165 is 56102818556.

65581820165 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 65581820165 - 2¹⁶ = 65581754629 is a prime.

It is a super-3 number, since 3×65581820165³ (a number of 33 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65581820167) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 93554315 + ... + 93555015.

It is an arithmetic number, because the mean of its divisors is an integer number (2495054016).

Almost surely, 2^65581820165 is an apocalyptic number.

It is an amenable number.

65581820165 is a deficient number, since it is larger than the sum of its proper divisors (14259908347).

65581820165 is a wasteful number, since it uses less digits than its factorization.

65581820165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1661.

The product of its (nonzero) digits is 576000, while the sum is 47.

The spelling of 65581820165 in words is "sixty-five billion, five hundred eighty-one million, eight hundred twenty thousand, one hundred sixty-five".