86555566778 has 4 divisors (see below), whose sum is σ = 129833350170. Its totient is φ = 43277783388.

The previous prime is 86555566729. The next prime is 86555566787. The reversal of 86555566778 is 87766555568.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 65036730529 + 21518836249 = 255023^2 + 146693^2 .

It is a super-2 number, since 2×86555566778² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21638891693 + ... + 21638891696.

Almost surely, 2^86555566778 is an apocalyptic number.

86555566778 is a deficient number, since it is larger than the sum of its proper divisors (43277783392).

86555566778 is a wasteful number, since it uses less digits than its factorization.

86555566778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43277783391.

The product of its digits is 423360000, while the sum is 68.

The spelling of 86555566778 in words is "eighty-six billion, five hundred fifty-five million, five hundred sixty-six thousand, seven hundred seventy-eight".