21100000218 has 64 divisors (see below), whose sum is σ = 46642839552. Its totient is φ = 6310241280.

The previous prime is 21100000157. The next prime is 21100000219. The reversal of 21100000218 is 81200000112.

It is a junction number, because it is equal to n+sod(n) for n = 21100000197 and 21100000206.

It is not an unprimeable number, because it can be changed into a prime (21100000219) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 1611205 + ... + 1624247.

It is an arithmetic number, because the mean of its divisors is an integer number (728794368).

Almost surely, 2^21100000218 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21100000218, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23321419776).

21100000218 is an abundant number, since it is smaller than the sum of its proper divisors (25542839334).

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

21100000218 is a wasteful number, since it uses less digits than its factorization.

21100000218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13379.

The product of its (nonzero) digits is 32, while the sum is 15.

The spelling of 21100000218 in words is "twenty-one billion, one hundred million, two hundred eighteen", and thus it is an aban number.