20505133 has 8 divisors (see below), whose sum is σ = 22423680. Its totient is φ = 18595680.

The previous prime is 20505127. The next prime is 20505151. The reversal of 20505133 is 33150502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20505133 - 2⁵ = 20505101 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 20505133.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20505103) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2988 + ... + 7066.

It is an arithmetic number, because the mean of its divisors is an integer number (2802960).

Almost surely, 2^20505133 is an apocalyptic number.

It is an amenable number.

20505133 is a deficient number, since it is larger than the sum of its proper divisors (1918547).

20505133 is a wasteful number, since it uses less digits than its factorization.

20505133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4547.

The product of its (nonzero) digits is 450, while the sum is 19.

The square root of 20505133 is about 4528.2593786134. The cubic root of 20505133 is about 273.7080245336.

Adding to 20505133 its reverse (33150502), we get a palindrome (53655635).

The spelling of 20505133 in words is "twenty million, five hundred five thousand, one hundred thirty-three".