1998807588 has 36 divisors (see below), whose sum is σ = 5078738028. Its totient is φ = 662814720.

The previous prime is 1998807529. The next prime is 1998807607. The reversal of 1998807588 is 8857088991.

It can be written as a sum of positive squares in 2 ways, for example, as 433972224 + 1564835364 = 20832^2 + 39558^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 136893 + ... + 150788.

Almost surely, 2^1998807588 is an apocalyptic number.

1998807588 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

1998807588 is an abundant number, since it is smaller than the sum of its proper divisors (3079930440).

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

1998807588 is a wasteful number, since it uses less digits than its factorization.

1998807588 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 287884 (or 287879 counting only the distinct ones).

The product of its (nonzero) digits is 11612160, while the sum is 63.

The square root of 1998807588 is about 44708.0259908666. The cubic root of 1998807588 is about 1259.6706092871.

The spelling of 1998807588 in words is "one billion, nine hundred ninety-eight million, eight hundred seven thousand, five hundred eighty-eight".