21102110988 has 72 divisors (see below), whose sum is σ = 57834588672. Its totient is φ = 5866191936.

The previous prime is 21102110969. The next prime is 21102111007. The reversal of 21102110988 is 88901120112.

It is an interprime number because it is at equal distance from previous prime (21102110969) and next prime (21102111007).

It is a super-3 number, since 3×21102110988³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 23245 + ... + 206747.

It is an arithmetic number, because the mean of its divisors is an integer number (803258176).

Almost surely, 2^21102110988 is an apocalyptic number.

21102110988 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 21102110988, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28917294336).

21102110988 is an abundant number, since it is smaller than the sum of its proper divisors (36732477684).

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

21102110988 is a wasteful number, since it uses less digits than its factorization.

21102110988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 183591 (or 183552 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 33.

The spelling of 21102110988 in words is "twenty-one billion, one hundred two million, one hundred ten thousand, nine hundred eighty-eight".