20388805 has 16 divisors (see below), whose sum is σ = 25937280. Its totient is φ = 15342912.

The previous prime is 20388803. The next prime is 20388811. The reversal of 20388805 is 50888302.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20388805 - 2¹ = 20388803 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20388803) 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, 14232 + ... + 15598.

It is an arithmetic number, because the mean of its divisors is an integer number (1621080).

Almost surely, 2^20388805 is an apocalyptic number.

It is an amenable number.

20388805 is a deficient number, since it is larger than the sum of its proper divisors (5548475).

20388805 is a wasteful number, since it uses less digits than its factorization.

20388805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1548.

The product of its (nonzero) digits is 15360, while the sum is 34.

The square root of 20388805 is about 4515.3964388523. The cubic root of 20388805 is about 273.1894501834.

The spelling of 20388805 in words is "twenty million, three hundred eighty-eight thousand, eight hundred five".