20330181 has 24 divisors (see below), whose sum is σ = 31463640. Its totient is φ = 12604416.

The previous prime is 20330153. The next prime is 20330201. The reversal of 20330181 is 18103302.

It can be written as a sum of positive squares in 4 ways, for example, as 6200100 + 14130081 = 2490^2 + 3759^2 .

It is not a de Polignac number, because 20330181 - 2⁶ = 20330117 is a prime.

It is a super-2 number, since 2×20330181² = 826632518985522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20330081) 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 23 ways as a sum of consecutive naturals, for example, 12871 + ... + 14363.

It is an arithmetic number, because the mean of its divisors is an integer number (1310985).

Almost surely, 2^20330181 is an apocalyptic number.

It is an amenable number.

20330181 is a deficient number, since it is larger than the sum of its proper divisors (11133459).

20330181 is a wasteful number, since it uses less digits than its factorization.

20330181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1605 (or 1602 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 20330181 is about 4508.9001984963. The cubic root of 20330181 is about 272.9273646474.

Adding to 20330181 its reverse (18103302), we get a palindrome (38433483).

The spelling of 20330181 in words is "twenty million, three hundred thirty thousand, one hundred eighty-one".