1998670 has 16 divisors (see below), whose sum is σ = 3615840. Its totient is φ = 795424.

The previous prime is 1998643. The next prime is 1998679. The reversal of 1998670 is 768991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1998679) 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, 2319 + ... + 3061.

It is an arithmetic number, because the mean of its divisors is an integer number (225990).

2^1998670 is an apocalyptic number.

1998670 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1998670 is a deficient number, since it is larger than the sum of its proper divisors (1617170).

1998670 is a wasteful number, since it uses less digits than its factorization.

1998670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1019.

The product of its (nonzero) digits is 27216, while the sum is 40.

The square root of 1998670 is about 1413.7432581625. The cubic root of 1998670 is about 125.9641705465.

It can be divided in two parts, 19 and 98670, that added together give a palindrome (98689).

The spelling of 1998670 in words is "one million, nine hundred ninety-eight thousand, six hundred seventy".