1998129 has 32 divisors (see below), whose sum is σ = 3352320. Its totient is φ = 1032192.

The previous prime is 1998127. The next prime is 1998133. The reversal of 1998129 is 9218991.

It is a happy number.

It is not a de Polignac number, because 1998129 - 2¹ = 1998127 is a prime.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (1998127) 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 31 ways as a sum of consecutive naturals, for example, 10257 + ... + 10449.

It is an arithmetic number, because the mean of its divisors is an integer number (104760).

2^1998129 is an apocalyptic number.

It is an amenable number.

1998129 is a deficient number, since it is larger than the sum of its proper divisors (1354191).

1998129 is a wasteful number, since it uses less digits than its factorization.

1998129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249.

The product of its digits is 11664, while the sum is 39.

The square root of 1998129 is about 1413.5519091990. The cubic root of 1998129 is about 125.9528041936.

The spelling of 1998129 in words is "one million, nine hundred ninety-eight thousand, one hundred twenty-nine".