561165206500 has 24 divisors (see below), whose sum is σ = 1225584812088. Its totient is φ = 224466082400.

The previous prime is 561165206491. The next prime is 561165206507. The reversal of 561165206500 is 5602561165.

It can be written as a sum of positive squares in 4 ways, for example, as 112187483136 + 448977723364 = 334944^2 + 670058^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 561165206500.

It is not an unprimeable number, because it can be changed into a prime (561165206507) 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, 561164707 + ... + 561165706.

It is an arithmetic number, because the mean of its divisors is an integer number (51066033837).

Almost surely, 2^561165206500 is an apocalyptic number.

561165206500 is a gapful number since it is divisible by the number (50) formed by its first and last digit.

It is an amenable number.

561165206500 is an abundant number, since it is smaller than the sum of its proper divisors (664419605588).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

561165206500 is a wasteful number, since it uses less digits than its factorization.

561165206500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1122330432 (or 1122330420 counting only the distinct ones).

The product of its (nonzero) digits is 54000, while the sum is 37.

Adding to 561165206500 its reverse (5602561165), we get a palindrome (566767767665).

The spelling of 561165206500 in words is "five hundred sixty-one billion, one hundred sixty-five million, two hundred six thousand, five hundred".