20385663 has 4 divisors (see below), whose sum is σ = 27180888. Its totient is φ = 13590440.

The previous prime is 20385653. The next prime is 20385671. The reversal of 20385663 is 36658302.

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

It is a cyclic number.

It is not a de Polignac number, because 20385663 - 2¹² = 20381567 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20385653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3397608 + ... + 3397613.

It is an arithmetic number, because the mean of its divisors is an integer number (6795222).

Almost surely, 2^20385663 is an apocalyptic number.

20385663 is a deficient number, since it is larger than the sum of its proper divisors (6795225).

20385663 is an equidigital number, since it uses as much as digits as its factorization.

20385663 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6795224.

The product of its (nonzero) digits is 25920, while the sum is 33.

The square root of 20385663 is about 4515.0485047228. The cubic root of 20385663 is about 273.1754162508.

The spelling of 20385663 in words is "twenty million, three hundred eighty-five thousand, six hundred sixty-three".