28365556657 has 2 divisors, whose sum is σ = 28365556658. Its totient is φ = 28365556656.

The previous prime is 28365556621. The next prime is 28365556691. The reversal of 28365556657 is 75665556382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23397985296 + 4967571361 = 152964^2 + 70481^2 .

It is a cyclic number.

It is not a de Polignac number, because 28365556657 - 2⁷ = 28365556529 is a prime.

It is a super-2 number, since 2×28365556657² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28365556157) 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, 14182778328 + 14182778329.

It is an arithmetic number, because the mean of its divisors is an integer number (14182778329).

Almost surely, 2^28365556657 is an apocalyptic number.

It is an amenable number.

28365556657 is a deficient number, since it is larger than the sum of its proper divisors (1).

28365556657 is an equidigital number, since it uses as much as digits as its factorization.

28365556657 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 45360000, while the sum is 58.

The spelling of 28365556657 in words is "twenty-eight billion, three hundred sixty-five million, five hundred fifty-six thousand, six hundred fifty-seven".