1605998 has 8 divisors (see below), whose sum is σ = 2513808. Its totient is φ = 768064.

The previous prime is 1605979. The next prime is 1606009. The reversal of 1605998 is 8995061.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17411 + ... + 17502.

It is an arithmetic number, because the mean of its divisors is an integer number (314226).

2^1605998 is an apocalyptic number.

1605998 is a deficient number, since it is larger than the sum of its proper divisors (907810).

1605998 is a wasteful number, since it uses less digits than its factorization.

1605998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34938.

The product of its (nonzero) digits is 19440, while the sum is 38.

The square root of 1605998 is about 1267.2797639038. The cubic root of 1605998 is about 117.1066794319.

The spelling of 1605998 in words is "one million, six hundred five thousand, nine hundred ninety-eight".