25778327761 has 2 divisors, whose sum is σ = 25778327762. Its totient is φ = 25778327760.

The previous prime is 25778327749. The next prime is 25778327801. The reversal of 25778327761 is 16772387752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24315724225 + 1462603536 = 155935^2 + 38244^2 .

It is a cyclic number.

It is not a de Polignac number, because 25778327761 - 2⁷ = 25778327633 is a prime.

It is not a weakly prime, because it can be changed into another prime (25778321761) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12889163880 + 12889163881.

It is an arithmetic number, because the mean of its divisors is an integer number (12889163881).

Almost surely, 2^25778327761 is an apocalyptic number.

It is an amenable number.

25778327761 is a deficient number, since it is larger than the sum of its proper divisors (1).

25778327761 is an equidigital number, since it uses as much as digits as its factorization.

25778327761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6914880, while the sum is 55.

It can be divided in two parts, 2577 and 8327761, that added together give a palindrome (8330338).

The spelling of 25778327761 in words is "twenty-five billion, seven hundred seventy-eight million, three hundred twenty-seven thousand, seven hundred sixty-one".