1657606609 has 2 divisors, whose sum is σ = 1657606610. Its totient is φ = 1657606608.

The previous prime is 1657606597. The next prime is 1657606627. The reversal of 1657606609 is 9066067561.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1646736400 + 10870209 = 40580^2 + 3297^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1657606609 is a prime.

It is not a weakly prime, because it can be changed into another prime (1657606649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 828803304 + 828803305.

It is an arithmetic number, because the mean of its divisors is an integer number (828803305).

Almost surely, 2^1657606609 is an apocalyptic number.

It is an amenable number.

1657606609 is a deficient number, since it is larger than the sum of its proper divisors (1).

1657606609 is an equidigital number, since it uses as much as digits as its factorization.

1657606609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 408240, while the sum is 46.

The square root of 1657606609 is about 40713.7152443743. The cubic root of 1657606609 is about 1183.4788195828.

The spelling of 1657606609 in words is "one billion, six hundred fifty-seven million, six hundred six thousand, six hundred nine".