25435242557 has 2 divisors, whose sum is σ = 25435242558. Its totient is φ = 25435242556.

The previous prime is 25435242493. The next prime is 25435242559. The reversal of 25435242557 is 75524253452.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24886324516 + 548918041 = 157754^2 + 23429^2 .

It is a cyclic number.

It is not a de Polignac number, because 25435242557 - 2⁶ = 25435242493 is a prime.

Together with 25435242559, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25435242559) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12717621278 + 12717621279.

It is an arithmetic number, because the mean of its divisors is an integer number (12717621279).

Almost surely, 2^25435242557 is an apocalyptic number.

It is an amenable number.

25435242557 is a deficient number, since it is larger than the sum of its proper divisors (1).

25435242557 is an equidigital number, since it uses as much as digits as its factorization.

25435242557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1680000, while the sum is 44.

The spelling of 25435242557 in words is "twenty-five billion, four hundred thirty-five million, two hundred forty-two thousand, five hundred fifty-seven".