20505486 has 16 divisors (see below), whose sum is σ = 41165568. Its totient is φ = 6809400.

The previous prime is 20505473. The next prime is 20505487. The reversal of 20505486 is 68450502.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20505487) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 4680 + ... + 7931.

It is an arithmetic number, because the mean of its divisors is an integer number (2572848).

Almost surely, 2^20505486 is an apocalyptic number.

20505486 is an abundant number, since it is smaller than the sum of its proper divisors (20660082).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20505486 is a wasteful number, since it uses less digits than its factorization.

20505486 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12887.

The product of its (nonzero) digits is 9600, while the sum is 30.

The square root of 20505486 is about 4528.2983558948. The cubic root of 20505486 is about 273.7095951709.

Adding to 20505486 its reverse (68450502), we get a palindrome (88955988).

The spelling of 20505486 in words is "twenty million, five hundred five thousand, four hundred eighty-six".