21102028116 has 24 divisors (see below), whose sum is σ = 53025609504. Its totient is φ = 6492931680.

The previous prime is 21102028111. The next prime is 21102028127. The reversal of 21102028116 is 61182020112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21102028111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 67634550 + ... + 67634861.

It is an arithmetic number, because the mean of its divisors is an integer number (2209400396).

Almost surely, 2^21102028116 is an apocalyptic number.

21102028116 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21102028116 is an abundant number, since it is smaller than the sum of its proper divisors (31923581388).

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

21102028116 is a wasteful number, since it uses less digits than its factorization.

21102028116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135269431 (or 135269429 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 24.

Adding to 21102028116 its reverse (61182020112), we get a palindrome (82284048228).

The spelling of 21102028116 in words is "twenty-one billion, one hundred two million, twenty-eight thousand, one hundred sixteen".