20305000 has 80 divisors (see below), whose sum is σ = 49484160. Its totient is φ = 7800000.

The previous prime is 20304997. The next prime is 20305003. The reversal of 20305000 is 50302.

It is an interprime number because it is at equal distance from previous prime (20304997) and next prime (20305003).

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20305003) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 154935 + ... + 155065.

It is an arithmetic number, because the mean of its divisors is an integer number (618552).

Almost surely, 2^20305000 is an apocalyptic number.

20305000 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 20305000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24742080).

20305000 is an abundant number, since it is smaller than the sum of its proper divisors (29179160).

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

20305000 is a wasteful number, since it uses less digits than its factorization.

20305000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188 (or 169 counting only the distinct ones).

The product of its (nonzero) digits is 30, while the sum is 10.

The square root of 20305000 is about 4506.1069672168. The cubic root of 20305000 is about 272.8146353119.

Adding to 20305000 its reverse (50302), we get a palindrome (20355302).

The spelling of 20305000 in words is "twenty million, three hundred five thousand".