20881938 has 72 divisors (see below), whose sum is σ = 53491536. Its totient is φ = 5414640.

The previous prime is 20881921. The next prime is 20881963. The reversal of 20881938 is 83918802.

It is a junction number, because it is equal to n+sod(n) for n = 20881896 and 20881905.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 35281 + ... + 35867.

It is an arithmetic number, because the mean of its divisors is an integer number (742938).

Almost surely, 2^20881938 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20881938, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26745768).

20881938 is an abundant number, since it is smaller than the sum of its proper divisors (32609598).

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

20881938 is a wasteful number, since it uses less digits than its factorization.

20881938 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 628 (or 610 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 39.

The square root of 20881938 is about 4569.6759184870. The cubic root of 20881938 is about 275.3744233099.

The spelling of 20881938 in words is "twenty million, eight hundred eighty-one thousand, nine hundred thirty-eight".