1999868416 has 80 divisors (see below), whose sum is σ = 4918060224. Its totient is φ = 791138304.

The previous prime is 1999868407. The next prime is 1999868417. The reversal of 1999868416 is 6148689991.

It is not an unprimeable number, because it can be changed into a prime (1999868417) 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, 25131 + ... + 68053.

Almost surely, 2^1999868416 is an apocalyptic number.

1999868416 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1999868416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2459030112).

1999868416 is an abundant number, since it is smaller than the sum of its proper divisors (2918191808).

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

1999868416 is an equidigital number, since it uses as much as digits as its factorization.

1999868416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42961 (or 42945 counting only the distinct ones).

The product of its digits is 6718464, while the sum is 61.

The square root of 1999868416 is about 44719.8883719537. Note that the first 3 decimals coincide. The cubic root of 1999868416 is about 1259.8934183803.

The spelling of 1999868416 in words is "one billion, nine hundred ninety-nine million, eight hundred sixty-eight thousand, four hundred sixteen".