20017940 has 48 divisors (see below), whose sum is σ = 44029440. Its totient is φ = 7635840.

The previous prime is 20017939. The next prime is 20017951. The reversal of 20017940 is 4971002.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 51266 + ... + 51654.

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

Almost surely, 2^20017940 is an apocalyptic number.

20017940 is a gapful number since it is divisible by the number (20) 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 20017940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22014720).

20017940 is an abundant number, since it is smaller than the sum of its proper divisors (24011500).

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

20017940 is a wasteful number, since it uses less digits than its factorization.

20017940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512 (or 510 counting only the distinct ones).

The product of its (nonzero) digits is 504, while the sum is 23.

The square root of 20017940 is about 4474.1412583869. The cubic root of 20017940 is about 271.5228984911.

Adding to 20017940 its reverse (4971002), we get a palindrome (24988942).

The spelling of 20017940 in words is "twenty million, seventeen thousand, nine hundred forty".