20548813 has 2 divisors, whose sum is σ = 20548814. Its totient is φ = 20548812.

The previous prime is 20548807. The next prime is 20548817. The reversal of 20548813 is 31884502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11710084 + 8838729 = 3422^2 + 2973^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20548813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20548817) 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 as a sum of consecutive naturals, namely, 10274406 + 10274407.

It is an arithmetic number, because the mean of its divisors is an integer number (10274407).

Almost surely, 2^20548813 is an apocalyptic number.

It is an amenable number.

20548813 is a deficient number, since it is larger than the sum of its proper divisors (1).

20548813 is an equidigital number, since it uses as much as digits as its factorization.

20548813 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7680, while the sum is 31.

The square root of 20548813 is about 4533.0798581097. The cubic root of 20548813 is about 273.9022374867.

The spelling of 20548813 in words is "twenty million, five hundred forty-eight thousand, eight hundred thirteen".