20006500 has 24 divisors (see below), whose sum is σ = 43695288. Its totient is φ = 8002400.

The previous prime is 20006489. The next prime is 20006507. The reversal of 20006500 is 560002.

It can be written as a sum of positive squares in 4 ways, for example, as 1205604 + 18800896 = 1098^2 + 4336^2 .

It is not an unprimeable number, because it can be changed into a prime (20006507) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19507 + ... + 20506.

It is an arithmetic number, because the mean of its divisors is an integer number (1820637).

Almost surely, 2^20006500 is an apocalyptic number.

20006500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20006500 is an abundant number, since it is smaller than the sum of its proper divisors (23688788).

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

20006500 is a wasteful number, since it uses less digits than its factorization.

20006500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40032 (or 40020 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 20006500 is about 4472.8626180557. The cubic root of 20006500 is about 271.4711646652.

Adding to 20006500 its reverse (560002), we get a palindrome (20566502).

The spelling of 20006500 in words is "twenty million, six thousand, five hundred".