409657 has 2 divisors, whose sum is σ = 409658. Its totient is φ = 409656.

The previous prime is 409639. The next prime is 409691. The reversal of 409657 is 756904.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 212521 + 197136 = 461^2 + 444^2 .

It is a cyclic number.

It is not a de Polignac number, because 409657 - 2⁷ = 409529 is a prime.

409657 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (400657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 204828 + 204829.

It is an arithmetic number, because the mean of its divisors is an integer number (204829).

2⁴⁰⁹⁶⁵⁷ is an apocalyptic number.

It is an amenable number.

409657 is a deficient number, since it is larger than the sum of its proper divisors (1).

409657 is an equidigital number, since it uses as much as digits as its factorization.

409657 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 409657 is about 640.0445297009. The cubic root of 409657 is about 74.2688661072.

The spelling of 409657 in words is "four hundred nine thousand, six hundred fifty-seven".