1668921099228 has 120 divisors (see below), whose sum is σ = 4440616432560. Its totient is φ = 546412227840.

The previous prime is 1668921099217. The next prime is 1668921099233. The reversal of 1668921099228 is 8229901298661.

It is a congruent number.

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 39 ways as a sum of consecutive naturals, for example, 22768798 + ... + 22841978.

It is an arithmetic number, because the mean of its divisors is an integer number (37005136938).

Almost surely, 2^{1668921099228} is an apocalyptic number.

1668921099228 is a gapful number since it is divisible by the number (18) 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 1668921099228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2220308216280).

1668921099228 is an abundant number, since it is smaller than the sum of its proper divisors (2771695333332).

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

1668921099228 is a wasteful number, since it uses less digits than its factorization.

1668921099228 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74449 (or 74438 counting only the distinct ones).

The product of its (nonzero) digits is 13436928, while the sum is 63.

The spelling of 1668921099228 in words is "one trillion, six hundred sixty-eight billion, nine hundred twenty-one million, ninety-nine thousand, two hundred twenty-eight".