20105455 has 4 divisors (see below), whose sum is σ = 24126552. Its totient is φ = 16084360.

The previous prime is 20105447. The next prime is 20105479. The reversal of 20105455 is 55450102.

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

It is not a de Polignac number, because 20105455 - 2³ = 20105447 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2010541 + ... + 2010550.

It is an arithmetic number, because the mean of its divisors is an integer number (6031638).

Almost surely, 2^20105455 is an apocalyptic number.

20105455 is a deficient number, since it is larger than the sum of its proper divisors (4021097).

20105455 is an equidigital number, since it uses as much as digits as its factorization.

20105455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4021096.

The product of its (nonzero) digits is 1000, while the sum is 22.

The square root of 20105455 is about 4483.9106815368. The cubic root of 20105455 is about 271.9180071129.

Adding to 20105455 its reverse (55450102), we get a palindrome (75555557).

The spelling of 20105455 in words is "twenty million, one hundred five thousand, four hundred fifty-five".