1998813186 has 80 divisors (see below), whose sum is σ = 4842245760. Its totient is φ = 614109600.

The previous prime is 1998813127. The next prime is 1998813191. The reversal of 1998813186 is 6813188991.

It is a Harshad number since it is a multiple of its sum of digits (54).

1998813186 is a modest number, since divided by 813186 gives 1998 as remainder.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 105111 + ... + 122661.

It is an arithmetic number, because the mean of its divisors is an integer number (60528072).

Almost surely, 2^1998813186 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1998813186, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2421122880).

1998813186 is an abundant number, since it is smaller than the sum of its proper divisors (2843432574).

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

1998813186 is a wasteful number, since it uses less digits than its factorization.

1998813186 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17621 (or 17612 counting only the distinct ones).

The product of its digits is 746496, while the sum is 54.

The square root of 1998813186 is about 44708.0885970313. The cubic root of 1998813186 is about 1259.6717852598.

The spelling of 1998813186 in words is "one billion, nine hundred ninety-eight million, eight hundred thirteen thousand, one hundred eighty-six".