20541636 has 18 divisors (see below), whose sum is σ = 51924782. Its totient is φ = 6847200.

The previous prime is 20541629. The next prime is 20541637. The reversal of 20541636 is 63614502.

20541636 is a `hidden beast` number, since 20 + 5 + 4 + 1 + 636 = 666.

It can be written as a sum of positive squares in only one way, i.e., 20520900 + 20736 = 4530^2 + 144^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is not an unprimeable number, because it can be changed into a prime (20541637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 285265 + ... + 285336.

Almost surely, 2^20541636 is an apocalyptic number.

It is an amenable number.

20541636 is an abundant number, since it is smaller than the sum of its proper divisors (31383146).

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

20541636 is a wasteful number, since it uses less digits than its factorization.

20541636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 570611 (or 570606 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 20541636 is about 4532.2881638307. The cubic root of 20541636 is about 273.8703455349.

The spelling of 20541636 in words is "twenty million, five hundred forty-one thousand, six hundred thirty-six".