78725123315257 has 2 divisors, whose sum is σ = 78725123315258. Its totient is φ = 78725123315256.

The previous prime is 78725123315203. The next prime is 78725123315281. The reversal of 78725123315257 is 75251332152787.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 56660787256896 + 22064336058361 = 7527336^2 + 4697269^2 .

It is a cyclic number.

It is not a de Polignac number, because 78725123315257 - 2³¹ = 78722975831609 is a prime.

It is not a weakly prime, because it can be changed into another prime (78725123015257) 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, 39362561657628 + 39362561657629.

It is an arithmetic number, because the mean of its divisors is an integer number (39362561657629).

Almost surely, 2^{78725123315257} is an apocalyptic number.

It is an amenable number.

78725123315257 is a deficient number, since it is larger than the sum of its proper divisors (1).

78725123315257 is an equidigital number, since it uses as much as digits as its factorization.

78725123315257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24696000, while the sum is 58.

The spelling of 78725123315257 in words is "seventy-eight trillion, seven hundred twenty-five billion, one hundred twenty-three million, three hundred fifteen thousand, two hundred fifty-seven".