20906500 has 24 divisors (see below), whose sum is σ = 45660888. Its totient is φ = 8362400.

The previous prime is 20906491. The next prime is 20906503. The reversal of 20906500 is 560902.

It can be written as a sum of positive squares in 4 ways, for example, as 3717184 + 17189316 = 1928^2 + 4146^2 .

It is a super-3 number, since 3×20906500³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20906503) 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, 20407 + ... + 21406.

It is an arithmetic number, because the mean of its divisors is an integer number (1902537).

Almost surely, 2^20906500 is an apocalyptic number.

20906500 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20906500 is an abundant number, since it is smaller than the sum of its proper divisors (24754388).

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

20906500 is a wasteful number, since it uses less digits than its factorization.

20906500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41832 (or 41820 counting only the distinct ones).

The product of its (nonzero) digits is 540, while the sum is 22.

The square root of 20906500 is about 4572.3626277888. The cubic root of 20906500 is about 275.4823490590.

The spelling of 20906500 in words is "twenty million, nine hundred six thousand, five hundred".