25185978167257 has 2 divisors, whose sum is σ = 25185978167258. Its totient is φ = 25185978167256.

The previous prime is 25185978167197. The next prime is 25185978167281. The reversal of 25185978167257 is 75276187958152.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17877979671696 + 7307998495561 = 4228236^2 + 2703331^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25185978167257 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 25185978167257.

It is not a weakly prime, because it can be changed into another prime (25185978467257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12592989083628 + 12592989083629.

It is an arithmetic number, because the mean of its divisors is an integer number (12592989083629).

Almost surely, 2^{25185978167257} is an apocalyptic number.

It is an amenable number.

25185978167257 is a deficient number, since it is larger than the sum of its proper divisors (1).

25185978167257 is an equidigital number, since it uses as much as digits as its factorization.

25185978167257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 592704000, while the sum is 73.

The spelling of 25185978167257 in words is "twenty-five trillion, one hundred eighty-five billion, nine hundred seventy-eight million, one hundred sixty-seven thousand, two hundred fifty-seven".