1999687944 has 64 divisors (see below), whose sum is σ = 5192294400. Its totient is φ = 641301824.

The previous prime is 1999687913. The next prime is 1999687973. The reversal of 1999687944 is 4497869991.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 51529 + ... + 81575.

It is an arithmetic number, because the mean of its divisors is an integer number (81129600).

Almost surely, 2^1999687944 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1999687944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2596147200).

1999687944 is an abundant number, since it is smaller than the sum of its proper divisors (3192606456).

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

1999687944 is a wasteful number, since it uses less digits than its factorization.

1999687944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30162 (or 30158 counting only the distinct ones).

The product of its digits is 35271936, while the sum is 66.

The square root of 1999687944 is about 44717.8705217500. The cubic root of 1999687944 is about 1259.8555188327.

The spelling of 1999687944 in words is "one billion, nine hundred ninety-nine million, six hundred eighty-seven thousand, nine hundred forty-four".