20187306 has 40 divisors (see below), whose sum is σ = 46805220. Its totient is φ = 6495552.

The previous prime is 20187289. The next prime is 20187317. The reversal of 20187306 is 60378102.

It can be written as a sum of positive squares in 2 ways, for example, as 20169081 + 18225 = 4491^2 + 135^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 20187306.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2550 + ... + 6846.

Almost surely, 2^20187306 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20187306, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23402610).

20187306 is an abundant number, since it is smaller than the sum of its proper divisors (26617914).

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

20187306 is a wasteful number, since it uses less digits than its factorization.

20187306 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4340 (or 4331 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 20187306 is about 4493.0285999535. The cubic root of 20187306 is about 272.2865078652.

The spelling of 20187306 in words is "twenty million, one hundred eighty-seven thousand, three hundred six".