1608639 has 4 divisors (see below), whose sum is σ = 2144856. Its totient is φ = 1072424.

The previous prime is 1608637. The next prime is 1608653. The reversal of 1608639 is 9368061.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1608639 - 2¹ = 1608637 is a prime.

It is a D-number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1608637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 268104 + ... + 268109.

It is an arithmetic number, because the mean of its divisors is an integer number (536214).

2^1608639 is an apocalyptic number.

1608639 is a deficient number, since it is larger than the sum of its proper divisors (536217).

1608639 is an equidigital number, since it uses as much as digits as its factorization.

1608639 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 536216.

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 1608639 is about 1268.3213315245. The cubic root of 1608639 is about 117.1708367063.

The spelling of 1608639 in words is "one million, six hundred eight thousand, six hundred thirty-nine".