1999545912 has 384 divisors, whose sum is σ = 7044710400. Its totient is φ = 517321728.

The previous prime is 1999545907. The next prime is 1999545979. The reversal of 1999545912 is 2195459991.

1999545912 is a `hidden beast` number, since 1 + 9 + 9 + 9 + 545 + 91 + 2 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 15744393 + ... + 15744519.

It is an arithmetic number, because the mean of its divisors is an integer number (18345600).

Almost surely, 2^1999545912 is an apocalyptic number.

1999545912 is a gapful number since it is divisible by the number (12) 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 1999545912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3522355200).

1999545912 is an abundant number, since it is smaller than the sum of its proper divisors (5045164488).

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

1999545912 is a wasteful number, since it uses less digits than its factorization.

1999545912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257 (or 241 counting only the distinct ones).

The product of its digits is 1312200, while the sum is 54.

The square root of 1999545912 is about 44716.2824036167. The cubic root of 1999545912 is about 1259.8256901726.

The spelling of 1999545912 in words is "one billion, nine hundred ninety-nine million, five hundred forty-five thousand, nine hundred twelve".