66055221216555 has 32 divisors (see below), whose sum is σ = 111443708352000. Its totient is φ = 33317426829312.

The previous prime is 66055221216547. The next prime is 66055221216557. The reversal of 66055221216555 is 55561212255066.

It is not a de Polignac number, because 66055221216555 - 2³ = 66055221216547 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66055221216498 and 66055221216507.

It is not an unprimeable number, because it can be changed into a prime (66055221216557) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 200678455 + ... + 201007344.

It is an arithmetic number, because the mean of its divisors is an integer number (3482615886000).

Almost surely, 2^{66055221216555} is an apocalyptic number.

66055221216555 is a deficient number, since it is larger than the sum of its proper divisors (45388487135445).

66055221216555 is a wasteful number, since it uses less digits than its factorization.

66055221216555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401686403.

The product of its (nonzero) digits is 5400000, while the sum is 51.

The spelling of 66055221216555 in words is "sixty-six trillion, fifty-five billion, two hundred twenty-one million, two hundred sixteen thousand, five hundred fifty-five".