66853812578 has 48 divisors (see below), whose sum is σ = 121135798080. Its totient is φ = 27558153504.

The previous prime is 66853812541. The next prime is 66853812589. The reversal of 66853812578 is 87521835866.

It is a hoax number, since the sum of its digits (59) coincides with the sum of the digits of its distinct prime factors.

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 in 23 ways as a sum of consecutive naturals, for example, 702725 + ... + 792167.

It is an arithmetic number, because the mean of its divisors is an integer number (2523662460).

Almost surely, 2^66853812578 is an apocalyptic number.

66853812578 is a deficient number, since it is larger than the sum of its proper divisors (54281985502).

66853812578 is a wasteful number, since it uses less digits than its factorization.

66853812578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 89751 (or 89744 counting only the distinct ones).

The product of its digits is 19353600, while the sum is 59.

The spelling of 66853812578 in words is "sixty-six billion, eight hundred fifty-three million, eight hundred twelve thousand, five hundred seventy-eight".