2000021840 has 20 divisors (see below), whose sum is σ = 4650050964. Its totient is φ = 800008704.

The previous prime is 2000021819. The next prime is 2000021843. The reversal of 2000021840 is 481200002.

It can be written as a sum of positive squares in 2 ways, for example, as 374964496 + 1625057344 = 19364^2 + 40312^2 .

It is a tau number, because it is divible by the number of its divisors (20).

2000021840 is a modest number, since divided by 21840 gives 2000 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2000021843) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 12500057 + ... + 12500216.

Almost surely, 2^2000021840 is an apocalyptic number.

2000021840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2000021840 is an abundant number, since it is smaller than the sum of its proper divisors (2650029124).

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

2000021840 is a wasteful number, since it uses less digits than its factorization.

2000021840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25000286 (or 25000280 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 2000021840 is about 44721.6037279523. The cubic root of 2000021840 is about 1259.9256359908.

Adding to 2000021840 its reverse (481200002), we get a palindrome (2481221842).

The spelling of 2000021840 in words is "two billion, twenty-one thousand, eight hundred forty".