20187385 has 8 divisors (see below), whose sum is σ = 24879816. Its totient is φ = 15713280.

The previous prime is 20187383. The next prime is 20187397. The reversal of 20187385 is 58378102.

It can be written as a sum of positive squares in 4 ways, for example, as 3606201 + 16581184 = 1899^2 + 4072^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20187385 - 2¹ = 20187383 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20187385.

It is not an unprimeable number, because it can be changed into a prime (20187383) 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 7 ways as a sum of consecutive naturals, for example, 54376 + ... + 54745.

It is an arithmetic number, because the mean of its divisors is an integer number (3109977).

Almost surely, 2^20187385 is an apocalyptic number.

It is an amenable number.

20187385 is a deficient number, since it is larger than the sum of its proper divisors (4692431).

20187385 is a wasteful number, since it uses less digits than its factorization.

20187385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109163.

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 20187385 is about 4493.0373913423. The cubic root of 20187385 is about 272.2868630489.

The spelling of 20187385 in words is "twenty million, one hundred eighty-seven thousand, three hundred eighty-five".