257440901 has 2 divisors, whose sum is σ = 257440902. Its totient is φ = 257440900.

The previous prime is 257440879. The next prime is 257440903. The reversal of 257440901 is 109044752.

It is a happy number.

257440901 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 249324100 + 8116801 = 15790^2 + 2849^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257440901 is a prime.

Together with 257440903, 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 (257440903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128720450 + 128720451.

It is an arithmetic number, because the mean of its divisors is an integer number (128720451).

Almost surely, 2^257440901 is an apocalyptic number.

It is an amenable number.

257440901 is a deficient number, since it is larger than the sum of its proper divisors (1).

257440901 is an equidigital number, since it uses as much as digits as its factorization.

257440901 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 257440901 is about 16044.9649734738. The cubic root of 257440901 is about 636.1494883831.

The spelling of 257440901 in words is "two hundred fifty-seven million, four hundred forty thousand, nine hundred one".