20688896 has 26 divisors (see below), whose sum is σ = 41380932. Its totient is φ = 10342400.

The previous prime is 20688869. The next prime is 20688907. The reversal of 20688896 is 69888602.

It is a self number, because there is not a number n which added to its sum of digits gives 20688896.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1571 + ... + 6621.

Almost surely, 2^20688896 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 20688896, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20690466).

20688896 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20688896 is an frugal number, since it uses more digits than its factorization.

20688896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5075 (or 5053 counting only the distinct ones).

The product of its (nonzero) digits is 331776, while the sum is 47.

The square root of 20688896 is about 4548.5048092752. The cubic root of 20688896 is about 274.5232334132.

The spelling of 20688896 in words is "twenty million, six hundred eighty-eight thousand, eight hundred ninety-six".