1608139009 has 4 divisors (see below), whose sum is σ = 1608307204. Its totient is φ = 1607970816.

The previous prime is 1608138991. The next prime is 1608139019. The reversal of 1608139009 is 9009318061.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9009318061 = 4451 ⋅2024111.

It can be written as a sum of positive squares in 2 ways, for example, as 1030217409 + 577921600 = 32097^2 + 24040^2 .

It is a cyclic number.

It is not a de Polignac number, because 1608139009 - 2¹⁷ = 1608007937 is a prime.

It is a super-3 number, since 3×1608139009³ (a number of 29 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1608139019) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68832 + ... + 89185.

It is an arithmetic number, because the mean of its divisors is an integer number (402076801).

Almost surely, 2^1608139009 is an apocalyptic number.

It is an amenable number.

1608139009 is a deficient number, since it is larger than the sum of its proper divisors (168195).

1608139009 is a wasteful number, since it uses less digits than its factorization.

1608139009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168194.

The product of its (nonzero) digits is 11664, while the sum is 37.

The square root of 1608139009 is about 40101.6085587598. The cubic root of 1608139009 is about 1171.5869591840.

The spelling of 1608139009 in words is "one billion, six hundred eight million, one hundred thirty-nine thousand, nine".