28117557617749 has 2 divisors, whose sum is σ = 28117557617750. Its totient is φ = 28117557617748.

The previous prime is 28117557617731. The next prime is 28117557617777. The reversal of 28117557617749 is 94771675571182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17375616917649 + 10741940700100 = 4168407^2 + 3277490^2 .

It is a cyclic number.

It is not a de Polignac number, because 28117557617749 - 2²³ = 28117549229141 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28117557317749) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14058778808874 + 14058778808875.

It is an arithmetic number, because the mean of its divisors is an integer number (14058778808875).

Almost surely, 2^{28117557617749} is an apocalyptic number.

It is an amenable number.

28117557617749 is a deficient number, since it is larger than the sum of its proper divisors (1).

28117557617749 is an equidigital number, since it uses as much as digits as its factorization.

28117557617749 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 207446400, while the sum is 70.

The spelling of 28117557617749 in words is "twenty-eight trillion, one hundred seventeen billion, five hundred fifty-seven million, six hundred seventeen thousand, seven hundred forty-nine".