25520191 has 2 divisors, whose sum is σ = 25520192. Its totient is φ = 25520190.

The previous prime is 25520171. The next prime is 25520221. The reversal of 25520191 is 19102552.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25520191 - 2⁷ = 25520063 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25520141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12760095 + 12760096.

It is an arithmetic number, because the mean of its divisors is an integer number (12760096).

Almost surely, 2^25520191 is an apocalyptic number.

25520191 is a deficient number, since it is larger than the sum of its proper divisors (1).

25520191 is an equidigital number, since it uses as much as digits as its factorization.

25520191 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 900, while the sum is 25.

The square root of 25520191 is about 5051.7512804967. The cubic root of 25520191 is about 294.4159314135.

The spelling of 25520191 in words is "twenty-five million, five hundred twenty thousand, one hundred ninety-one".