1257409 has 2 divisors, whose sum is σ = 1257410. Its totient is φ = 1257408.

The previous prime is 1257397. The next prime is 1257437. The reversal of 1257409 is 9047521.

It is a happy number.

It is an a-pointer prime, because the next prime (1257437) can be obtained adding 1257409 to its sum of digits (28).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 760384 + 497025 = 872^2 + 705^2 .

It is a cyclic number.

It is not a de Polignac number, because 1257409 - 2⁷ = 1257281 is a prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (1257499) 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, 628704 + 628705.

It is an arithmetic number, because the mean of its divisors is an integer number (628705).

2^1257409 is an apocalyptic number.

It is an amenable number.

1257409 is a deficient number, since it is larger than the sum of its proper divisors (1).

1257409 is an equidigital number, since it uses as much as digits as its factorization.

1257409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 1257409 is about 1121.3424989717. The cubic root of 1257409 is about 107.9341448082.

The spelling of 1257409 in words is "one million, two hundred fifty-seven thousand, four hundred nine".