20525181 has 4 divisors (see below), whose sum is σ = 27366912. Its totient is φ = 13683452.

The previous prime is 20525159. The next prime is 20525189. The reversal of 20525181 is 18152502.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20525181 - 2⁷ = 20525053 is a prime.

It is a super-2 number, since 2×20525181² = 842566110165522, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20525189) 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 3 ways as a sum of consecutive naturals, for example, 3420861 + ... + 3420866.

It is an arithmetic number, because the mean of its divisors is an integer number (6841728).

Almost surely, 2^20525181 is an apocalyptic number.

It is an amenable number.

20525181 is a deficient number, since it is larger than the sum of its proper divisors (6841731).

20525181 is an equidigital number, since it uses as much as digits as its factorization.

20525181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6841730.

The product of its (nonzero) digits is 800, while the sum is 24.

The square root of 20525181 is about 4530.4724919152. The cubic root of 20525181 is about 273.7971975084.

Adding to 20525181 its reverse (18152502), we get a palindrome (38677683).

It can be divided in two parts, 20525 and 181, that added together give a triangular number (20706 = T₂₀₃).

The spelling of 20525181 in words is "twenty million, five hundred twenty-five thousand, one hundred eighty-one".