20247181 has 4 divisors (see below), whose sum is σ = 20579164. Its totient is φ = 19915200.

The previous prime is 20247131. The next prime is 20247193. The reversal of 20247181 is 18174202.

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 10692900 + 9554281 = 3270^2 + 3091^2 .

It is a cyclic number.

It is not a de Polignac number, because 20247181 - 2⁷ = 20247053 is a prime.

It is a super-2 number, since 2×20247181² = 819896676893522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20247131) 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, 165900 + ... + 166021.

It is an arithmetic number, because the mean of its divisors is an integer number (5144791).

Almost surely, 2^20247181 is an apocalyptic number.

It is an amenable number.

20247181 is a deficient number, since it is larger than the sum of its proper divisors (331983).

20247181 is an equidigital number, since it uses as much as digits as its factorization.

20247181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331982.

The product of its (nonzero) digits is 896, while the sum is 25.

The square root of 20247181 is about 4499.6867668761. The cubic root of 20247181 is about 272.5554402812. Note that the first 3 decimals are identical.

The spelling of 20247181 in words is "twenty million, two hundred forty-seven thousand, one hundred eighty-one".