20418400 has 36 divisors (see below), whose sum is σ = 49848372. Its totient is φ = 8167040.

The previous prime is 20418379. The next prime is 20418401. The reversal of 20418400 is 481402.

It is a super-2 number, since 2×20418400² = 833822117120000, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20418401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11962 + ... + 13561.

It is an arithmetic number, because the mean of its divisors is an integer number (1384677).

Almost surely, 2^20418400 is an apocalyptic number.

20418400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20418400 is an abundant number, since it is smaller than the sum of its proper divisors (29429972).

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

20418400 is a wasteful number, since it uses less digits than its factorization.

20418400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25543 (or 25530 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 20418400 is about 4518.6723713941. The cubic root of 20418400 is about 273.3215673433.

Adding to 20418400 its reverse (481402), we get a palindrome (20899802).

The spelling of 20418400 in words is "twenty million, four hundred eighteen thousand, four hundred".