6561261127061 has 8 divisors (see below), whose sum is σ = 6569633661240. Its totient is φ = 6552893020608.

The previous prime is 6561261127021. The next prime is 6561261127093. The reversal of 6561261127061 is 1607211621656.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 214363444036 + 6346897683025 = 462994^2 + 2519305^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6561261127061 - 2⁶ = 6561261126997 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6561261127021) 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, 1863755 + ... + 4073831.

It is an arithmetic number, because the mean of its divisors is an integer number (821204207655).

Almost surely, 2^{6561261127061} is an apocalyptic number.

It is an amenable number.

6561261127061 is a deficient number, since it is larger than the sum of its proper divisors (8372534179).

6561261127061 is a wasteful number, since it uses less digits than its factorization.

6561261127061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2213863.

The product of its (nonzero) digits is 181440, while the sum is 44.

The spelling of 6561261127061 in words is "six trillion, five hundred sixty-one billion, two hundred sixty-one million, one hundred twenty-seven thousand, sixty-one".