21912058168 has 128 divisors (see below), whose sum is σ = 55531607040. Its totient is φ = 7827840000.

The previous prime is 21912058151. The next prime is 21912058219. The reversal of 21912058168 is 86185021912.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1200148 + ... + 1218268.

It is an arithmetic number, because the mean of its divisors is an integer number (433840680).

Almost surely, 2^21912058168 is an apocalyptic number.

21912058168 is a gapful number since it is divisible by the number (28) 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 21912058168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27765803520).

21912058168 is an abundant number, since it is smaller than the sum of its proper divisors (33619548872).

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

21912058168 is a wasteful number, since it uses less digits than its factorization.

21912058168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18309 (or 18305 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 43.

The spelling of 21912058168 in words is "twenty-one billion, nine hundred twelve million, fifty-eight thousand, one hundred sixty-eight".