20478500 has 48 divisors (see below), whose sum is σ = 51123072. Its totient is φ = 7020000.

The previous prime is 20478499. The next prime is 20478509. The reversal of 20478500 is 587402.

It is a self number, because there is not a number n which added to its sum of digits gives 20478500.

It is not an unprimeable number, because it can be changed into a prime (20478509) 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 15 ways as a sum of consecutive naturals, for example, 575 + ... + 6425.

It is an arithmetic number, because the mean of its divisors is an integer number (1065064).

Almost surely, 2^20478500 is an apocalyptic number.

20478500 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 20478500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25561536).

20478500 is an abundant number, since it is smaller than the sum of its proper divisors (30644572).

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

20478500 is a wasteful number, since it uses less digits than its factorization.

20478500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5877 (or 5865 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 26.

The square root of 20478500 is about 4525.3176684074. The cubic root of 20478500 is about 273.5894717116.

The spelling of 20478500 in words is "twenty million, four hundred seventy-eight thousand, five hundred".