55505808217 has 8 divisors (see below), whose sum is σ = 55679125320. Its totient is φ = 55332648960.

The previous prime is 55505808199. The next prime is 55505808229. The reversal of 55505808217 is 71280850555.

It can be written as a sum of positive squares in 4 ways, for example, as 8423751961 + 47082056256 = 91781^2 + 216984^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55505808217 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55505808257) 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, 685593 + ... + 762265.

It is an arithmetic number, because the mean of its divisors is an integer number (6959890665).

Almost surely, 2^55505808217 is an apocalyptic number.

It is an amenable number.

55505808217 is a deficient number, since it is larger than the sum of its proper divisors (173317103).

55505808217 is a wasteful number, since it uses less digits than its factorization.

55505808217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78923.

The product of its (nonzero) digits is 560000, while the sum is 46.

The spelling of 55505808217 in words is "fifty-five billion, five hundred five million, eight hundred eight thousand, two hundred seventeen".