395128609 has 2 divisors, whose sum is σ = 395128610. Its totient is φ = 395128608.

The previous prime is 395128529. The next prime is 395128649. The reversal of 395128609 is 906821593.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 335915584 + 59213025 = 18328^2 + 7695^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-395128609 is a prime.

It is a super-2 number, since 2×395128609² = 312253235300549762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (395128649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 197564304 + 197564305.

It is an arithmetic number, because the mean of its divisors is an integer number (197564305).

Almost surely, 2^395128609 is an apocalyptic number.

It is an amenable number.

395128609 is a deficient number, since it is larger than the sum of its proper divisors (1).

395128609 is an equidigital number, since it uses as much as digits as its factorization.

395128609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 116640, while the sum is 43.

The square root of 395128609 is about 19877.8421615627. The cubic root of 395128609 is about 733.8030150713.

The spelling of 395128609 in words is "three hundred ninety-five million, one hundred twenty-eight thousand, six hundred nine".