2100545845 has 4 divisors (see below), whose sum is σ = 2520655020. Its totient is φ = 1680436672.

The previous prime is 2100545809. The next prime is 2100545849. The reversal of 2100545845 is 5485450012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1459392804 + 641153041 = 38202^2 + 25321^2 .

It is a cyclic number.

It is not a de Polignac number, because 2100545845 - 2⁷ = 2100545717 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2100545845.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2100545849) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 210054580 + ... + 210054589.

It is an arithmetic number, because the mean of its divisors is an integer number (630163755).

Almost surely, 2^2100545845 is an apocalyptic number.

It is an amenable number.

2100545845 is a deficient number, since it is larger than the sum of its proper divisors (420109175).

2100545845 is an equidigital number, since it uses as much as digits as its factorization.

2100545845 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420109174.

The product of its (nonzero) digits is 32000, while the sum is 34.

The square root of 2100545845 is about 45831.7122198157. The cubic root of 2100545845 is about 1280.6901073971.

Adding to 2100545845 its reverse (5485450012), we get a palindrome (7585995857).

The spelling of 2100545845 in words is "two billion, one hundred million, five hundred forty-five thousand, eight hundred forty-five".