1999831680 has 768 divisors, whose sum is σ = 8982005760. Its totient is φ = 413061120.

The previous prime is 1999831657. The next prime is 1999831709. The reversal of 1999831680 is 861389991.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 11974957 + ... + 11975123.

It is an arithmetic number, because the mean of its divisors is an integer number (11695320).

Almost surely, 2^1999831680 is an apocalyptic number.

1999831680 is a gapful number since it is divisible by the number (10) 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 1999831680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4491002880).

1999831680 is an abundant number, since it is smaller than the sum of its proper divisors (6982174080).

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

1999831680 is a wasteful number, since it uses less digits than its factorization.

1999831680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 219 (or 195 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 54.

The square root of 1999831680 is about 44719.4776355896. The cubic root of 1999831680 is about 1259.8857039181.

The spelling of 1999831680 in words is "one billion, nine hundred ninety-nine million, eight hundred thirty-one thousand, six hundred eighty".