20385578 has 4 divisors (see below), whose sum is σ = 30578370. Its totient is φ = 10192788.

The previous prime is 20385577. The next prime is 20385581. The reversal of 20385578 is 87558302.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 19562929 + 822649 = 4423^2 + 907^2 .

It is not an unprimeable number, because it can be changed into a prime (20385571) 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 as a sum of consecutive naturals, namely, 5096393 + ... + 5096396.

Almost surely, 2^20385578 is an apocalyptic number.

20385578 is a deficient number, since it is larger than the sum of its proper divisors (10192792).

20385578 is a wasteful number, since it uses less digits than its factorization.

20385578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10192791.

The product of its (nonzero) digits is 67200, while the sum is 38.

The square root of 20385578 is about 4515.0390917466. The cubic root of 20385578 is about 273.1750365731.

The spelling of 20385578 in words is "twenty million, three hundred eighty-five thousand, five hundred seventy-eight".