66166506083520 has 168 divisors, whose sum is σ = 228272783453520. Its totient is φ = 17591095019520.

The previous prime is 66166506083467. The next prime is 66166506083539. The reversal of 66166506083520 is 2538060566166.

66166506083520 is a `hidden beast` number, since 6 + 6 + 1 + 6 + 6 + 5 + 0 + 608 + 3 + 5 + 20 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 33751375 + ... + 35657934.

Almost surely, 2^{66166506083520} is an apocalyptic number.

66166506083520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66166506083520 is an abundant number, since it is smaller than the sum of its proper divisors (162106277370000).

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

66166506083520 is a wasteful number, since it uses less digits than its factorization.

66166506083520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69409663 (or 69409650 counting only the distinct ones).

The product of its (nonzero) digits is 9331200, while the sum is 54.

The spelling of 66166506083520 in words is "sixty-six trillion, one hundred sixty-six billion, five hundred six million, eighty-three thousand, five hundred twenty".