1999026816 has 128 divisors (see below), whose sum is σ = 5509109760. Its totient is φ = 641571840.

The previous prime is 1999026773. The next prime is 1999026833. The reversal of 1999026816 is 6186209991.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×1999026816² = 7992216422174195712, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3654255 + ... + 3654801.

It is an arithmetic number, because the mean of its divisors is an integer number (43039920).

Almost surely, 2^1999026816 is an apocalyptic number.

1999026816 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 1999026816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2754554880).

1999026816 is an abundant number, since it is smaller than the sum of its proper divisors (3510082944).

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

1999026816 is a wasteful number, since it uses less digits than its factorization.

1999026816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 902 (or 890 counting only the distinct ones).

The product of its (nonzero) digits is 419904, while the sum is 51.

The square root of 1999026816 is about 44710.4776981861. The cubic root of 1999026816 is about 1259.7166609054.

The spelling of 1999026816 in words is "one billion, nine hundred ninety-nine million, twenty-six thousand, eight hundred sixteen".