2100564 has 72 divisors (see below), whose sum is σ = 5809440. Its totient is φ = 637632.

The previous prime is 2100563. The next prime is 2100569. The reversal of 2100564 is 4650012.

It is a happy number.

2100564 is a `hidden beast` number, since 2 + 100 + 564 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2100563) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25267 + ... + 25349.

2^2100564 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2100564, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2904720).

2100564 is an abundant number, since it is smaller than the sum of its proper divisors (3708876).

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

2100564 is a wasteful number, since it uses less digits than its factorization.

2100564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149 (or 144 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 2100564 is about 1449.3322600425. The cubic root of 2100564 is about 128.0693797051.

Adding to 2100564 its reverse (4650012), we get a palindrome (6750576).

The spelling of 2100564 in words is "two million, one hundred thousand, five hundred sixty-four".