20528181 has 16 divisors (see below), whose sum is σ = 30481920. Its totient is φ = 13654080.

The previous prime is 20528171. The next prime is 20528203. The reversal of 20528181 is 18182502.

It is not a de Polignac number, because 20528181 - 2²³ = 12139573 is a prime.

It is a super-2 number, since 2×20528181² = 842812430337522, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

20528181 is a modest number, since divided by 8181 gives 2052 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20528171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22861 + ... + 23741.

It is an arithmetic number, because the mean of its divisors is an integer number (1905120).

Almost surely, 2^20528181 is an apocalyptic number.

It is an amenable number.

20528181 is a deficient number, since it is larger than the sum of its proper divisors (9953739).

20528181 is an equidigital number, since it uses as much as digits as its factorization.

20528181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1753 (or 1747 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 27.

The square root of 20528181 is about 4530.8035711119. The cubic root of 20528181 is about 273.8105364339.

The spelling of 20528181 in words is "twenty million, five hundred twenty-eight thousand, one hundred eighty-one".