1998887550 has 96 divisors (see below), whose sum is σ = 5499826560. Its totient is φ = 476342400.

The previous prime is 1998887549. The next prime is 1998887567. The reversal of 1998887550 is 557888991.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 87084 + ... + 107616.

It is an arithmetic number, because the mean of its divisors is an integer number (57289860).

Almost surely, 2^1998887550 is an apocalyptic number.

1998887550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1998887550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2749913280).

1998887550 is an abundant number, since it is smaller than the sum of its proper divisors (3500939010).

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

1998887550 is a wasteful number, since it uses less digits than its factorization.

1998887550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20618 (or 20613 counting only the distinct ones).

The product of its (nonzero) digits is 7257600, while the sum is 60.

The square root of 1998887550 is about 44708.9202508851. The cubic root of 1998887550 is about 1259.6874067081.

The spelling of 1998887550 in words is "one billion, nine hundred ninety-eight million, eight hundred eighty-seven thousand, five hundred fifty".