25803508121 has 2 divisors, whose sum is σ = 25803508122. Its totient is φ = 25803508120.

The previous prime is 25803508057. The next prime is 25803508139. The reversal of 25803508121 is 12180530852.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 22674336400 + 3129171721 = 150580^2 + 55939^2 .

It is a cyclic number.

It is not a de Polignac number, because 25803508121 - 2⁶ = 25803508057 is a prime.

It is not a weakly prime, because it can be changed into another prime (25803508151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12901754060 + 12901754061.

It is an arithmetic number, because the mean of its divisors is an integer number (12901754061).

Almost surely, 2^25803508121 is an apocalyptic number.

It is an amenable number.

25803508121 is a deficient number, since it is larger than the sum of its proper divisors (1).

25803508121 is an equidigital number, since it uses as much as digits as its factorization.

25803508121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19200, while the sum is 35.

The spelling of 25803508121 in words is "twenty-five billion, eight hundred three million, five hundred eight thousand, one hundred twenty-one".