20388400 has 30 divisors (see below), whose sum is σ = 48984092. Its totient is φ = 8155200.

The previous prime is 20388397. The next prime is 20388409. The reversal of 20388400 is 488302.

It is a super-3 number, since 3×20388400³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (20388409) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 25086 + ... + 25885.

Almost surely, 2^20388400 is an apocalyptic number.

20388400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20388400 is an abundant number, since it is smaller than the sum of its proper divisors (28595692).

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

20388400 is a wasteful number, since it uses less digits than its factorization.

20388400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50989 (or 50978 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 25.

The square root of 20388400 is about 4515.3515920690. The cubic root of 20388400 is about 273.1876413075.

The spelling of 20388400 in words is "twenty million, three hundred eighty-eight thousand, four hundred".