20988884 has 48 divisors (see below), whose sum is σ = 44029440. Its totient is φ = 8567040.

The previous prime is 20988881. The next prime is 20988893. The reversal of 20988884 is 48888902.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (47).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20988881) 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, 53762 + ... + 54150.

It is an arithmetic number, because the mean of its divisors is an integer number (917280).

Almost surely, 2^20988884 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 20988884, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22014720).

20988884 is an abundant number, since it is smaller than the sum of its proper divisors (23040556).

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

20988884 is a wasteful number, since it uses less digits than its factorization.

20988884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 488 (or 486 counting only the distinct ones).

The product of its (nonzero) digits is 294912, while the sum is 47.

The square root of 20988884 is about 4581.3626793783. The cubic root of 20988884 is about 275.8437293620.

The spelling of 20988884 in words is "twenty million, nine hundred eighty-eight thousand, eight hundred eighty-four".