20318940 has 72 divisors (see below), whose sum is σ = 62112960. Its totient is φ = 5376384.

The previous prime is 20318939. The next prime is 20318953. The reversal of 20318940 is 4981302.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27901 + ... + 28619.

It is an arithmetic number, because the mean of its divisors is an integer number (862680).

Almost surely, 2^20318940 is an apocalyptic number.

20318940 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 20318940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31056480).

20318940 is an abundant number, since it is smaller than the sum of its proper divisors (41794020).

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

20318940 is a wasteful number, since it uses less digits than its factorization.

20318940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 891 (or 886 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 20318940 is about 4507.6534915630. The cubic root of 20318940 is about 272.8770528781.

The spelling of 20318940 in words is "twenty million, three hundred eighteen thousand, nine hundred forty".