20881024 has 32 divisors (see below), whose sum is σ = 42732900. Its totient is φ = 10156032.

The previous prime is 20881001. The next prime is 20881027. The reversal of 20881024 is 42018802.

It can be written as a sum of positive squares in 2 ways, for example, as 20866624 + 14400 = 4568^2 + 120^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a self number, because there is not a number n which added to its sum of digits gives 20881024.

It is not an unprimeable number, because it can be changed into a prime (20881027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2532 + ... + 6940.

Almost surely, 2^20881024 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 20881024, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21366450).

20881024 is an abundant number, since it is smaller than the sum of its proper divisors (21851876).

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

20881024 is an equidigital number, since it uses as much as digits as its factorization.

20881024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4460 (or 4448 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 25.

The square root of 20881024 is about 4569.5759103006. The cubic root of 20881024 is about 275.3704055491.

Adding to 20881024 its reverse (42018802), we get a palindrome (62899826).

The spelling of 20881024 in words is "twenty million, eight hundred eighty-one thousand, twenty-four".