2001780000 has 480 divisors, whose sum is σ = 7982694720. Its totient is φ = 483840000.

The previous prime is 2001779993. The next prime is 2001780007. The reversal of 2001780000 is 871002.

It is an interprime number because it is at equal distance from previous prime (2001779993) and next prime (2001780007).

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (2001780007) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 5939832 + ... + 5940168.

It is an arithmetic number, because the mean of its divisors is an integer number (16630614).

Almost surely, 2^2001780000 is an apocalyptic number.

2001780000 is a gapful number since it is divisible by the number (20) 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 2001780000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3991347360).

2001780000 is an abundant number, since it is smaller than the sum of its proper divisors (5980914720).

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

2001780000 is a wasteful number, since it uses less digits than its factorization.

2001780000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 387 (or 358 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 2001780000 is about 44741.2561289913. The cubic root of 2001780000 is about 1260.2947156408.

The spelling of 2001780000 in words is "two billion, one million, seven hundred eighty thousand".