257821453 has 2 divisors, whose sum is σ = 257821454. Its totient is φ = 257821452.

The previous prime is 257821423. The next prime is 257821457. The reversal of 257821453 is 354128752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 210308004 + 47513449 = 14502^2 + 6893^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257821453 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257821457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128910726 + 128910727.

It is an arithmetic number, because the mean of its divisors is an integer number (128910727).

Almost surely, 2^257821453 is an apocalyptic number.

It is an amenable number.

257821453 is a deficient number, since it is larger than the sum of its proper divisors (1).

257821453 is an equidigital number, since it uses as much as digits as its factorization.

257821453 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 67200, while the sum is 37.

The square root of 257821453 is about 16056.8195169529. The cubic root of 257821453 is about 636.4627884730.

The spelling of 257821453 in words is "two hundred fifty-seven million, eight hundred twenty-one thousand, four hundred fifty-three".