21100946688 has 144 divisors (see below), whose sum is σ = 62676398400. Its totient is φ = 7002408960.

The previous prime is 21100946687. The next prime is 21100946747. The reversal of 21100946688 is 88664900112.

21100946688 is a `hidden beast` number, since 2 + 1 + 100 + 9 + 466 + 88 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×21100946688² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100946687) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1576183 + ... + 1589513.

Almost surely, 2^21100946688 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21100946688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31338199200).

21100946688 is an abundant number, since it is smaller than the sum of its proper divisors (41575451712).

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

21100946688 is a wasteful number, since it uses less digits than its factorization.

21100946688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13585 (or 13565 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 45.

The spelling of 21100946688 in words is "twenty-one billion, one hundred million, nine hundred forty-six thousand, six hundred eighty-eight".