1666516504212 has 144 divisors (see below), whose sum is σ = 4894536285184. Its totient is φ = 468224064000.

The previous prime is 1666516504193. The next prime is 1666516504253. The reversal of 1666516504212 is 2124056156661.

It is a congruent number.

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 47 ways as a sum of consecutive naturals, for example, 74250912 + ... + 74273352.

Almost surely, 2^{1666516504212} is an apocalyptic number.

1666516504212 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1666516504212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2447268142592).

1666516504212 is an abundant number, since it is smaller than the sum of its proper divisors (3228019780972).

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

1666516504212 is a wasteful number, since it uses less digits than its factorization.

1666516504212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27350 (or 27345 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 45.

The spelling of 1666516504212 in words is "one trillion, six hundred sixty-six billion, five hundred sixteen million, five hundred four thousand, two hundred twelve".