20500145 has 16 divisors (see below), whose sum is σ = 26734080. Its totient is φ = 15033600.

The previous prime is 20500097. The next prime is 20500159. The reversal of 20500145 is 54100502.

It is not a de Polignac number, because 20500145 - 2²⁰ = 19451569 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 536 + ... + 6425.

It is an arithmetic number, because the mean of its divisors is an integer number (1670880).

Almost surely, 2^20500145 is an apocalyptic number.

It is an amenable number.

20500145 is a deficient number, since it is larger than the sum of its proper divisors (6233935).

20500145 is a wasteful number, since it uses less digits than its factorization.

20500145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7016.

The product of its (nonzero) digits is 200, while the sum is 17.

The square root of 20500145 is about 4527.7085816117. The cubic root of 20500145 is about 273.6858290124.

Adding to 20500145 its reverse (54100502), we get a palindrome (74600647).

The spelling of 20500145 in words is "twenty million, five hundred thousand, one hundred forty-five".