218168721787828 has 12 divisors (see below), whose sum is σ = 436337443575712. Its totient is φ = 93500880766200.

The previous prime is 218168721787817. The next prime is 218168721787903. The reversal of 218168721787828 is 828787127861812.

218168721787828 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3895870031898 + ... + 3895870031953.

Almost surely, 2^{218168721787828} is an apocalyptic number.

218168721787828 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

218168721787828 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

218168721787828 is a wasteful number, since it uses less digits than its factorization.

218168721787828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7791740063862 (or 7791740063860 counting only the distinct ones).

The product of its digits is 539492352, while the sum is 76.

The spelling of 218168721787828 in words is "two hundred eighteen trillion, one hundred sixty-eight billion, seven hundred twenty-one million, seven hundred eighty-seven thousand, eight hundred twenty-eight".