1998722 has 16 divisors (see below), whose sum is σ = 3341952. Its totient is φ = 888720.

The previous prime is 1998701. The next prime is 1998727. The reversal of 1998722 is 2278991.

It is not an unprimeable number, because it can be changed into a prime (1998727) 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 7 ways as a sum of consecutive naturals, for example, 68 + ... + 2000.

It is an arithmetic number, because the mean of its divisors is an integer number (208872).

2^1998722 is an apocalyptic number.

1998722 is a deficient number, since it is larger than the sum of its proper divisors (1343230).

1998722 is a wasteful number, since it uses less digits than its factorization.

1998722 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1993.

The product of its digits is 18144, while the sum is 38.

The square root of 1998722 is about 1413.7616489352. The cubic root of 1998722 is about 125.9652629530.

The spelling of 1998722 in words is "one million, nine hundred ninety-eight thousand, seven hundred twenty-two".