42561240065 has 16 divisors (see below), whose sum is σ = 51267012048. Its totient is φ = 33920065536.

The previous prime is 42561240061. The next prime is 42561240131. The reversal of 42561240065 is 56004216524.

It can be written as a sum of positive squares in 8 ways, for example, as 14283118144 + 28278121921 = 119512^2 + 168161^2 .

It is a cyclic number.

It is not a de Polignac number, because 42561240065 - 2² = 42561240061 is a prime.

It is a super-2 number, since 2×42561240065² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42561240061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6842837 + ... + 6849053.

It is an arithmetic number, because the mean of its divisors is an integer number (3204188253).

Almost surely, 2^42561240065 is an apocalyptic number.

It is an amenable number.

42561240065 is a deficient number, since it is larger than the sum of its proper divisors (8705771983).

42561240065 is a wasteful number, since it uses less digits than its factorization.

42561240065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11188.

The product of its (nonzero) digits is 57600, while the sum is 35.

Adding to 42561240065 its reverse (56004216524), we get a palindrome (98565456589).

The spelling of 42561240065 in words is "forty-two billion, five hundred sixty-one million, two hundred forty thousand, sixty-five".