20430181 has 8 divisors (see below), whose sum is σ = 21483000. Its totient is φ = 19400640.

The previous prime is 20430173. The next prime is 20430191. The reversal of 20430181 is 18103402.

It can be written as a sum of positive squares in 4 ways, for example, as 3132900 + 17297281 = 1770^2 + 4159^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20430181 - 2³ = 20430173 is a prime.

It is a super-2 number, since 2×20430181² = 834784591385522, 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 (20430121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4006 + ... + 7543.

It is an arithmetic number, because the mean of its divisors is an integer number (2685375).

Almost surely, 2^20430181 is an apocalyptic number.

It is an amenable number.

20430181 is a deficient number, since it is larger than the sum of its proper divisors (1052819).

20430181 is a wasteful number, since it uses less digits than its factorization.

20430181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11639.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 20430181 is about 4519.9757742714. The cubic root of 20430181 is about 273.3741242249.

Adding to 20430181 its reverse (18103402), we get a palindrome (38533583).

The spelling of 20430181 in words is "twenty million, four hundred thirty thousand, one hundred eighty-one".