1664352209 has 8 divisors (see below), whose sum is σ = 1802742312. Its totient is φ = 1527442560.

The previous prime is 1664352103. The next prime is 1664352229. The reversal of 1664352209 is 9022534661.

It can be written as a sum of positive squares in 4 ways, for example, as 866007184 + 798345025 = 29428^2 + 28255^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1664352209 - 2¹² = 1664348113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1664352229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 367772 + ... + 372269.

It is an arithmetic number, because the mean of its divisors is an integer number (225342789).

Almost surely, 2^1664352209 is an apocalyptic number.

It is an amenable number.

1664352209 is a deficient number, since it is larger than the sum of its proper divisors (138390103).

1664352209 is a wasteful number, since it uses less digits than its factorization.

1664352209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 740227.

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 1664352209 is about 40796.4729970619. The cubic root of 1664352209 is about 1185.0820286585.

The spelling of 1664352209 in words is "one billion, six hundred sixty-four million, three hundred fifty-two thousand, two hundred nine".