20385730 has 8 divisors (see below), whose sum is σ = 36694332. Its totient is φ = 8154288.

The previous prime is 20385719. The next prime is 20385731. The reversal of 20385730 is 3758302.

It can be written as a sum of positive squares in 2 ways, for example, as 18054001 + 2331729 = 4249^2 + 1527^2 .

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

It is not an unprimeable number, because it can be changed into a prime (20385731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1019277 + ... + 1019296.

Almost surely, 2^20385730 is an apocalyptic number.

20385730 is a deficient number, since it is larger than the sum of its proper divisors (16308602).

20385730 is a wasteful number, since it uses less digits than its factorization.

20385730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2038580.

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 20385730 is about 4515.0559243491. The cubic root of 20385730 is about 273.1757155254.

It can be divided in two parts, 20385 and 730, that added together give a triangular number (21115 = T₂₀₅).

The spelling of 20385730 in words is "twenty million, three hundred eighty-five thousand, seven hundred thirty".