1998731118 has 32 divisors (see below), whose sum is σ = 4118708736. Its totient is φ = 646287488.

The previous prime is 1998731113. The next prime is 1998731129. The reversal of 1998731118 is 8111378991.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1998731113) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 505 + ... + 63227.

It is an arithmetic number, because the mean of its divisors is an integer number (128709648).

Almost surely, 2^1998731118 is an apocalyptic number.

1998731118 is an abundant number, since it is smaller than the sum of its proper divisors (2119977618).

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

1998731118 is a wasteful number, since it uses less digits than its factorization.

1998731118 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62888.

The product of its digits is 108864, while the sum is 48.

The square root of 1998731118 is about 44707.1707671152. The cubic root of 1998731118 is about 1259.6545450028.

The spelling of 1998731118 in words is "one billion, nine hundred ninety-eight million, seven hundred thirty-one thousand, one hundred eighteen".