20388355 has 16 divisors (see below), whose sum is σ = 27899424. Its totient is φ = 14169600.

The previous prime is 20388353. The next prime is 20388367. The reversal of 20388355 is 55388302.

It is not a de Polignac number, because 20388355 - 2¹ = 20388353 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 20388355.

It is not an unprimeable number, because it can be changed into a prime (20388353) 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 15 ways as a sum of consecutive naturals, for example, 8121 + ... + 10330.

It is an arithmetic number, because the mean of its divisors is an integer number (1743714).

Almost surely, 2^20388355 is an apocalyptic number.

20388355 is a deficient number, since it is larger than the sum of its proper divisors (7511069).

20388355 is a wasteful number, since it uses less digits than its factorization.

20388355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18486.

The product of its (nonzero) digits is 28800, while the sum is 34.

The square root of 20388355 is about 4515.3466090656. The cubic root of 20388355 is about 273.1874403198.

The spelling of 20388355 in words is "twenty million, three hundred eighty-eight thousand, three hundred fifty-five".