6561870355365 has 64 divisors (see below), whose sum is σ = 12135698297856. Its totient is φ = 2998782369792.

The previous prime is 6561870355307. The next prime is 6561870355367. The reversal of 6561870355365 is 5635530781656.

It is not a de Polignac number, because 6561870355365 - 2⁶ = 6561870355301 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6561870355299 and 6561870355308.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6561870355367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 13315869 + ... + 13799858.

It is an arithmetic number, because the mean of its divisors is an integer number (189620285904).

Almost surely, 2^{6561870355365} is an apocalyptic number.

6561870355365 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

6561870355365 is a deficient number, since it is larger than the sum of its proper divisors (5573827942491).

6561870355365 is a wasteful number, since it uses less digits than its factorization.

6561870355365 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27115838.

The product of its (nonzero) digits is 68040000, while the sum is 60.

The spelling of 6561870355365 in words is "six trillion, five hundred sixty-one billion, eight hundred seventy million, three hundred fifty-five thousand, three hundred sixty-five".