561171665065 has 32 divisors (see below), whose sum is σ = 782183640960. Its totient is φ = 381971481600.

The previous prime is 561171665063. The next prime is 561171665069. The reversal of 561171665065 is 560566171165.

It is not a de Polignac number, because 561171665065 - 2¹ = 561171665063 is a prime.

It is not an unprimeable number, because it can be changed into a prime (561171665063) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1509126 + ... + 1843855.

It is an arithmetic number, because the mean of its divisors is an integer number (24443238780).

Almost surely, 2^561171665065 is an apocalyptic number.

561171665065 is a gapful number since it is divisible by the number (55) formed by its first and last digit.

It is an amenable number.

561171665065 is a deficient number, since it is larger than the sum of its proper divisors (221011975895).

561171665065 is a wasteful number, since it uses less digits than its factorization.

561171665065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3353193.

The product of its (nonzero) digits is 1134000, while the sum is 49.

The spelling of 561171665065 in words is "five hundred sixty-one billion, one hundred seventy-one million, six hundred sixty-five thousand, sixty-five".