1609641697 has 2 divisors, whose sum is σ = 1609641698. Its totient is φ = 1609641696.

The previous prime is 1609641689. The next prime is 1609641707. The reversal of 1609641697 is 7961469061.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1565072721 + 44568976 = 39561^2 + 6676^2 .

It is a cyclic number.

It is not a de Polignac number, because 1609641697 - 2³ = 1609641689 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1609641697.

It is not a weakly prime, because it can be changed into another prime (1609641647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 804820848 + 804820849.

It is an arithmetic number, because the mean of its divisors is an integer number (804820849).

Almost surely, 2^1609641697 is an apocalyptic number.

It is an amenable number.

1609641697 is a deficient number, since it is larger than the sum of its proper divisors (1).

1609641697 is an equidigital number, since it uses as much as digits as its factorization.

1609641697 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 489888, while the sum is 49.

The square root of 1609641697 is about 40120.3401904819. The cubic root of 1609641697 is about 1171.9517662844.

The spelling of 1609641697 in words is "one billion, six hundred nine million, six hundred forty-one thousand, six hundred ninety-seven".