66517879998 has 8 divisors (see below), whose sum is σ = 133035760008. Its totient is φ = 22172626664.

The previous prime is 66517879991. The next prime is 66517880057. The reversal of 66517879998 is 89997871566.

It is a sphenic number, since it is the product of 3 distinct primes.

66517879998 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66517879991) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5543156661 + ... + 5543156672.

It is an arithmetic number, because the mean of its divisors is an integer number (16629470001).

Almost surely, 2^66517879998 is an apocalyptic number.

66517879998 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66517879998 is a wasteful number, since it uses less digits than its factorization.

66517879998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11086313338.

The product of its digits is 411505920, while the sum is 75.

The spelling of 66517879998 in words is "sixty-six billion, five hundred seventeen million, eight hundred seventy-nine thousand, nine hundred ninety-eight".