25520237761 has 2 divisors, whose sum is σ = 25520237762. Its totient is φ = 25520237760.

The previous prime is 25520237753. The next prime is 25520237779. The reversal of 25520237761 is 16773202552.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24576519361 + 943718400 = 156769^2 + 30720^2 .

It is a cyclic number.

It is not a de Polignac number, because 25520237761 - 2³ = 25520237753 is a prime.

It is not a weakly prime, because it can be changed into another prime (25520237741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12760118880 + 12760118881.

It is an arithmetic number, because the mean of its divisors is an integer number (12760118881).

Almost surely, 2^25520237761 is an apocalyptic number.

It is an amenable number.

25520237761 is a deficient number, since it is larger than the sum of its proper divisors (1).

25520237761 is an equidigital number, since it uses as much as digits as its factorization.

25520237761 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 176400, while the sum is 40.

The spelling of 25520237761 in words is "twenty-five billion, five hundred twenty million, two hundred thirty-seven thousand, seven hundred sixty-one".