1591998 has 8 divisors (see below), whose sum is σ = 3184008. Its totient is φ = 530664.

The previous prime is 1591981. The next prime is 1592027. The reversal of 1591998 is 8991951.

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

1591998 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 132661 + ... + 132672.

It is an arithmetic number, because the mean of its divisors is an integer number (398001).

2^1591998 is an apocalyptic number.

1591998 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1591998 is a wasteful number, since it uses less digits than its factorization.

1591998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265338.

The product of its digits is 29160, while the sum is 42.

The square root of 1591998 is about 1261.7440310935. The cubic root of 1591998 is about 116.7654003195.

The spelling of 1591998 in words is "one million, five hundred ninety-one thousand, nine hundred ninety-eight".