20454505 has 4 divisors (see below), whose sum is σ = 24545412. Its totient is φ = 16363600.

The previous prime is 20454481. The next prime is 20454523. The reversal of 20454505 is 50545402.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2442969 + 18011536 = 1563^2 + 4244^2 .

It is not a de Polignac number, because 20454505 - 2¹⁹ = 19930217 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 20454505.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 2045446 + ... + 2045455.

It is an arithmetic number, because the mean of its divisors is an integer number (6136353).

Almost surely, 2^20454505 is an apocalyptic number.

It is an amenable number.

20454505 is a deficient number, since it is larger than the sum of its proper divisors (4090907).

20454505 is an equidigital number, since it uses as much as digits as its factorization.

20454505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4090906.

The product of its (nonzero) digits is 4000, while the sum is 25.

The square root of 20454505 is about 4522.6656962460. The cubic root of 20454505 is about 273.4825735003.

Adding to 20454505 its reverse (50545402), we get a palindrome (70999907).

The spelling of 20454505 in words is "twenty million, four hundred fifty-four thousand, five hundred five".