6505561556655 has 64 divisors (see below), whose sum is σ = 11938710970368. Its totient is φ = 2963283200640.

The previous prime is 6505561556633. The next prime is 6505561556693. The reversal of 6505561556655 is 5566551655056.

It is a happy number.

It is not a de Polignac number, because 6505561556655 - 2¹⁶ = 6505561491119 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 33051742 + ... + 33247988.

It is an arithmetic number, because the mean of its divisors is an integer number (186542358912).

Almost surely, 2^{6505561556655} is an apocalyptic number.

6505561556655 is a deficient number, since it is larger than the sum of its proper divisors (5433149413713).

6505561556655 is a wasteful number, since it uses less digits than its factorization.

6505561556655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197396.

The product of its (nonzero) digits is 101250000, while the sum is 60.

The spelling of 6505561556655 in words is "six trillion, five hundred five billion, five hundred sixty-one million, five hundred fifty-six thousand, six hundred fifty-five".