1668351666678 has 32 divisors (see below), whose sum is σ = 3686587831296. Its totient is φ = 500647728768.

The previous prime is 1668351666677. The next prime is 1668351666689. The reversal of 1668351666678 is 8766661538661.

It is a Harshad number since it is a multiple of its sum of digits (69).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1668351666677) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 355571326 + ... + 355576017.

It is an arithmetic number, because the mean of its divisors is an integer number (115205869728).

Almost surely, 2^{1668351666678} is an apocalyptic number.

1668351666678 is an abundant number, since it is smaller than the sum of its proper divisors (2018236164618).

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

1668351666678 is a wasteful number, since it uses less digits than its factorization.

1668351666678 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 711147388.

The product of its digits is 313528320, while the sum is 69.

The spelling of 1668351666678 in words is "one trillion, six hundred sixty-eight billion, three hundred fifty-one million, six hundred sixty-six thousand, six hundred seventy-eight".