55599786578 has 18 divisors (see below), whose sum is σ = 97020027351. Its totient is φ = 23827479564.

The previous prime is 55599786563. The next prime is 55599786631. The reversal of 55599786578 is 87568799555.

It can be written as a sum of positive squares in only one way, i.e., 27799893289 + 27799893289 = 166733^2 + 166733^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=166733.

It is a Duffinian number.

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, 2322353 + ... + 2346171.

Almost surely, 2^55599786578 is an apocalyptic number.

55599786578 is a deficient number, since it is larger than the sum of its proper divisors (41420240773).

55599786578 is an frugal number, since it uses more digits than its factorization.

55599786578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47654 (or 23828 counting only the distinct ones).

The product of its digits is 952560000, while the sum is 74.

The spelling of 55599786578 in words is "fifty-five billion, five hundred ninety-nine million, seven hundred eighty-six thousand, five hundred seventy-eight".