85559779778 has 18 divisors (see below), whose sum is σ = 141075073587. Its totient is φ = 38888740660.

The previous prime is 85559779769. The next prime is 85559779783. The reversal of 85559779778 is 87797795558.

It can be written as a sum of positive squares in only one way, i.e., 42779889889 + 42779889889 = 206833^2 + 206833^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=206833.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 85559779699 and 85559779708.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4540925 + ... + 4559727.

Almost surely, 2^85559779778 is an apocalyptic number.

85559779778 is a deficient number, since it is larger than the sum of its proper divisors (55515293809).

85559779778 is an frugal number, since it uses more digits than its factorization.

85559779778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37630 (or 18816 counting only the distinct ones).

The product of its digits is 1555848000, while the sum is 77.

The spelling of 85559779778 in words is "eighty-five billion, five hundred fifty-nine million, seven hundred seventy-nine thousand, seven hundred seventy-eight".