1999545856 has 160 divisors (see below), whose sum is σ = 5062033152. Its totient is φ = 766402560.

The previous prime is 1999545841. The next prime is 1999545857. The reversal of 1999545856 is 6585459991.

It is a junction number, because it is equal to n+sod(n) for n = 1999545794 and 1999545803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1999545857) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2641030 + ... + 2641786.

Almost surely, 2^1999545856 is an apocalyptic number.

1999545856 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 1999545856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2531016576).

1999545856 is an abundant number, since it is smaller than the sum of its proper divisors (3062487296).

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

1999545856 is an equidigital number, since it uses as much as digits as its factorization.

1999545856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 860 (or 844 counting only the distinct ones).

The product of its digits is 17496000, while the sum is 61.

The square root of 1999545856 is about 44716.2817774466. The cubic root of 1999545856 is about 1259.8256784116.

The spelling of 1999545856 in words is "one billion, nine hundred ninety-nine million, five hundred forty-five thousand, eight hundred fifty-six".