28378052557 has 2 divisors, whose sum is σ = 28378052558. Its totient is φ = 28378052556.

The previous prime is 28378052513. The next prime is 28378052567. The reversal of 28378052557 is 75525087382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27124113636 + 1253938921 = 164694^2 + 35411^2 .

It is a cyclic number.

It is not a de Polignac number, because 28378052557 - 2⁷ = 28378052429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28378052567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14189026278 + 14189026279.

It is an arithmetic number, because the mean of its divisors is an integer number (14189026279).

Almost surely, 2^28378052557 is an apocalyptic number.

It is an amenable number.

28378052557 is a deficient number, since it is larger than the sum of its proper divisors (1).

28378052557 is an equidigital number, since it uses as much as digits as its factorization.

28378052557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4704000, while the sum is 52.

The spelling of 28378052557 in words is "twenty-eight billion, three hundred seventy-eight million, fifty-two thousand, five hundred fifty-seven".