20938400 has 72 divisors (see below), whose sum is σ = 58433760. Its totient is φ = 7176960.

The previous prime is 20938387. The next prime is 20938403. The reversal of 20938400 is 483902.

It is a self number, because there is not a number n which added to its sum of digits gives 20938400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20938403) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3731 + ... + 7469.

It is an arithmetic number, because the mean of its divisors is an integer number (811580).

Almost surely, 2^20938400 is an apocalyptic number.

20938400 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 20938400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29216880).

20938400 is an abundant number, since it is smaller than the sum of its proper divisors (37495360).

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

20938400 is a wasteful number, since it uses less digits than its factorization.

20938400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3766 (or 3753 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 20938400 is about 4575.8496478796. The cubic root of 20938400 is about 275.6223919656.

The spelling of 20938400 in words is "twenty million, nine hundred thirty-eight thousand, four hundred".