2105512500 has 288 divisors, whose sum is σ = 7570015488. Its totient is φ = 443520000.

The previous prime is 2105512499. The next prime is 2105512511. The reversal of 2105512500 is 52155012.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3412192 + ... + 3412808.

It is an arithmetic number, because the mean of its divisors is an integer number (26284776).

Almost surely, 2^2105512500 is an apocalyptic number.

2105512500 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 2105512500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3785007744).

2105512500 is an abundant number, since it is smaller than the sum of its proper divisors (5464502988).

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

2105512500 is a wasteful number, since it uses less digits than its factorization.

2105512500 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 669 (or 647 counting only the distinct ones).

The product of its (nonzero) digits is 500, while the sum is 21.

The square root of 2105512500 is about 45885.8638362623. The cubic root of 2105512500 is about 1281.6986927408.

Adding to 2105512500 its reverse (52155012), we get a palindrome (2157667512).

It can be divided in two parts, 2105512 and 500, that added together give a palindrome (2106012).

The spelling of 2105512500 in words is "two billion, one hundred five million, five hundred twelve thousand, five hundred".