20128513 has 2 divisors, whose sum is σ = 20128514. Its totient is φ = 20128512.

The previous prime is 20128501. The next prime is 20128529. The reversal of 20128513 is 31582102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18215824 + 1912689 = 4268^2 + 1383^2 .

It is a cyclic number.

It is not a de Polignac number, because 20128513 - 2¹⁷ = 19997441 is a prime.

It is not a weakly prime, because it can be changed into another prime (20128553) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10064256 + 10064257.

It is an arithmetic number, because the mean of its divisors is an integer number (10064257).

Almost surely, 2^20128513 is an apocalyptic number.

It is an amenable number.

20128513 is a deficient number, since it is larger than the sum of its proper divisors (1).

20128513 is an equidigital number, since it uses as much as digits as its factorization.

20128513 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 20128513 is about 4486.4811378184. The cubic root of 20128513 is about 272.0219173876.

The spelling of 20128513 in words is "twenty million, one hundred twenty-eight thousand, five hundred thirteen".