27805778555 has 16 divisors (see below), whose sum is σ = 33594808320. Its totient is φ = 22093015392.

The previous prime is 27805778537. The next prime is 27805778557. The reversal of 27805778555 is 55587750872.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27805778555 is a prime.

It is a super-2 number, since 2×27805778555² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 27805778494 and 27805778503.

It is not an unprimeable number, because it can be changed into a prime (27805778557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 721382 + ... + 758948.

It is an arithmetic number, because the mean of its divisors is an integer number (2099675520).

Almost surely, 2^27805778555 is an apocalyptic number.

27805778555 is a deficient number, since it is larger than the sum of its proper divisors (5789029765).

27805778555 is a wasteful number, since it uses less digits than its factorization.

27805778555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38578.

The product of its (nonzero) digits is 27440000, while the sum is 59.

The spelling of 27805778555 in words is "twenty-seven billion, eight hundred five million, seven hundred seventy-eight thousand, five hundred fifty-five".