1998736 has 20 divisors (see below), whose sum is σ = 3947292. Its totient is φ = 980096.

The previous prime is 1998727. The next prime is 1998739. The reversal of 1998736 is 6378991.

It can be written as a sum of positive squares in 2 ways, for example, as 883600 + 1115136 = 940^2 + 1056^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1998692 and 1998701.

It is not an unprimeable number, because it can be changed into a prime (1998739) 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, 331 + ... + 2026.

2^1998736 is an apocalyptic number.

1998736 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1998736 is a deficient number, since it is larger than the sum of its proper divisors (1948556).

1998736 is a wasteful number, since it uses less digits than its factorization.

1998736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2418 (or 2412 counting only the distinct ones).

The product of its digits is 81648, while the sum is 43.

The square root of 1998736 is about 1413.7666002562. The cubic root of 1998736 is about 125.9655570592.

The spelling of 1998736 in words is "one million, nine hundred ninety-eight thousand, seven hundred thirty-six".