2105187840 has 640 divisors, whose sum is σ = 9035136000. Its totient is φ = 453869568.

The previous prime is 2105187839. The next prime is 2105187883. The reversal of 2105187840 is 487815012.

2105187840 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 2105187795 and 2105187804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 9192846 + ... + 9193074.

It is an arithmetic number, because the mean of its divisors is an integer number (14117400).

Almost surely, 2^2105187840 is an apocalyptic number.

2105187840 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 2105187840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4517568000).

2105187840 is an abundant number, since it is smaller than the sum of its proper divisors (6929948160).

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

2105187840 is a wasteful number, since it uses less digits than its factorization.

2105187840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 287 (or 265 counting only the distinct ones).

The product of its (nonzero) digits is 17920, while the sum is 36.

The square root of 2105187840 is about 45882.3260090419. The cubic root of 2105187840 is about 1281.6328120764.

The spelling of 2105187840 in words is "two billion, one hundred five million, one hundred eighty-seven thousand, eight hundred forty".