18425513 has 2 divisors, whose sum is σ = 18425514. Its totient is φ = 18425512.

The previous prime is 18425509. The next prime is 18425521. The reversal of 18425513 is 31552481.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17952169 + 473344 = 4237^2 + 688^2 .

It is a cyclic number.

It is not a de Polignac number, because 18425513 - 2² = 18425509 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (18425413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9212756 + 9212757.

It is an arithmetic number, because the mean of its divisors is an integer number (9212757).

Almost surely, 2^18425513 is an apocalyptic number.

It is an amenable number.

18425513 is a deficient number, since it is larger than the sum of its proper divisors (1).

18425513 is an equidigital number, since it uses as much as digits as its factorization.

18425513 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4800, while the sum is 29.

The square root of 18425513 is about 4292.4949621403. The cubic root of 18425513 is about 264.1231872678.

Adding to 18425513 its reverse (31552481), we get a palindrome (49977994).

The spelling of 18425513 in words is "eighteen million, four hundred twenty-five thousand, five hundred thirteen".