28131442517 has 2 divisors, whose sum is σ = 28131442518. Its totient is φ = 28131442516.

The previous prime is 28131442459. The next prime is 28131442523. The reversal of 28131442517 is 71524413182.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28129662961 + 1779556 = 167719^2 + 1334^2 .

It is a cyclic number.

It is not a de Polignac number, because 28131442517 - 2⁶ = 28131442453 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28131042517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14065721258 + 14065721259.

It is an arithmetic number, because the mean of its divisors is an integer number (14065721259).

Almost surely, 2^28131442517 is an apocalyptic number.

It is an amenable number.

28131442517 is a deficient number, since it is larger than the sum of its proper divisors (1).

28131442517 is an equidigital number, since it uses as much as digits as its factorization.

28131442517 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 38.

Adding to 28131442517 its reverse (71524413182), we get a palindrome (99655855699).

The spelling of 28131442517 in words is "twenty-eight billion, one hundred thirty-one million, four hundred forty-two thousand, five hundred seventeen".