20388445 has 16 divisors (see below), whose sum is σ = 30503808. Its totient is φ = 12709440.

The previous prime is 20388437. The next prime is 20388449. The reversal of 20388445 is 54488302.

It is not a de Polignac number, because 20388445 - 2³ = 20388437 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 20388445.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20388449) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 26094 + ... + 26863.

It is an arithmetic number, because the mean of its divisors is an integer number (1906488).

Almost surely, 2^20388445 is an apocalyptic number.

It is an amenable number.

20388445 is a deficient number, since it is larger than the sum of its proper divisors (10115363).

20388445 is a wasteful number, since it uses less digits than its factorization.

20388445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52980.

The product of its (nonzero) digits is 30720, while the sum is 34.

The square root of 20388445 is about 4515.3565750669. The cubic root of 20388445 is about 273.1878422949.

The spelling of 20388445 in words is "twenty million, three hundred eighty-eight thousand, four hundred forty-five".