21014681688 has 512 divisors, whose sum is σ = 79388467200. Its totient is φ = 4973529600.

The previous prime is 21014681683. The next prime is 21014681707. The reversal of 21014681688 is 88618641012.

21014681688 is a `hidden beast` number, since 2 + 101 + 468 + 1 + 6 + 88 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21014681683) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 17945343 + ... + 17946513.

It is an arithmetic number, because the mean of its divisors is an integer number (155055600).

Almost surely, 2^21014681688 is an apocalyptic number.

21014681688 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 21014681688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39694233600).

21014681688 is an abundant number, since it is smaller than the sum of its proper divisors (58373785512).

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

21014681688 is a wasteful number, since it uses less digits than its factorization.

21014681688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1300 (or 1290 counting only the distinct ones).

The product of its (nonzero) digits is 147456, while the sum is 45.

The spelling of 21014681688 in words is "twenty-one billion, fourteen million, six hundred eighty-one thousand, six hundred eighty-eight".