66618307551966 has 96 divisors (see below), whose sum is σ = 136610829312000. Its totient is φ = 21657250879488.

The previous prime is 66618307551881. The next prime is 66618307551979. The reversal of 66618307551966 is 66915570381666.

It is a self number, because there is not a number n which added to its sum of digits gives 66618307551966.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6424752030 + ... + 6424762398.

It is an arithmetic number, because the mean of its divisors is an integer number (1423029472000).

Almost surely, 2^{66618307551966} is an apocalyptic number.

66618307551966 is an abundant number, since it is smaller than the sum of its proper divisors (69992521760034).

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

66618307551966 is a wasteful number, since it uses less digits than its factorization.

66618307551966 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12126 (or 12079 counting only the distinct ones).

The product of its (nonzero) digits is 293932800, while the sum is 69.

The spelling of 66618307551966 in words is "sixty-six trillion, six hundred eighteen billion, three hundred seven million, five hundred fifty-one thousand, nine hundred sixty-six".