1668718820522 has 8 divisors (see below), whose sum is σ = 2695622710116. Its totient is φ = 770177917152.

The previous prime is 1668718820477. The next prime is 1668718820609. The reversal of 1668718820522 is 2250288178661.

It is a Cunningham number, because it is equal to 1291789²+1.

It can be written as a sum of positive squares in 2 ways, for example, as 1668718820521 + 1 = 1291789^2 + 1^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 32090746523 + ... + 32090746574.

Almost surely, 2^{1668718820522} is an apocalyptic number.

1668718820522 is a deficient number, since it is larger than the sum of its proper divisors (1026903889594).

1668718820522 is a wasteful number, since it uses less digits than its factorization.

1668718820522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64181493112.

The product of its (nonzero) digits is 5160960, while the sum is 56.

The spelling of 1668718820522 in words is "one trillion, six hundred sixty-eight billion, seven hundred eighteen million, eight hundred twenty thousand, five hundred twenty-two".