396551609 has 2 divisors, whose sum is σ = 396551610. Its totient is φ = 396551608.

The previous prime is 396551581. The next prime is 396551611. The reversal of 396551609 is 906155693.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 268861609 + 127690000 = 16397^2 + 11300^2 .

It is a cyclic number.

It is not a de Polignac number, because 396551609 - 2²⁰ = 395503033 is a prime.

Together with 396551611, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 396551609.

It is not a weakly prime, because it can be changed into another prime (396551669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198275804 + 198275805.

It is an arithmetic number, because the mean of its divisors is an integer number (198275805).

Almost surely, 2^396551609 is an apocalyptic number.

It is an amenable number.

396551609 is a deficient number, since it is larger than the sum of its proper divisors (1).

396551609 is an equidigital number, since it uses as much as digits as its factorization.

396551609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 218700, while the sum is 44.

The square root of 396551609 is about 19913.6036166235. The cubic root of 396551609 is about 734.6828557558.

The spelling of 396551609 in words is "three hundred ninety-six million, five hundred fifty-one thousand, six hundred nine".