20265181 has 2 divisors, whose sum is σ = 20265182.
Its totient is φ = 20265180.
The previous prime is 20265151. The next prime is 20265187. The reversal of 20265181 is 18156202.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 20169081 + 96100 = 4491^2 + 310^2
It is a cyclic number.
It is not a de Polignac number, because 20265181 - 215 = 20232413 is a prime.
It is a super-2 number, since 2×202651812 = 821355121925522, which contains 22 as substring.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (20265187) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10132590 + 10132591.
It is an arithmetic number, because the mean of its divisors is an integer number (10132591).
Almost surely, 220265181 is an apocalyptic number.
It is an amenable number.
20265181 is a deficient number, since it is larger than the sum of its proper divisors (1).
20265181 is an equidigital number, since it uses as much as digits as its factorization.
20265181 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 960, while the sum is 25.
The square root of 20265181 is about 4501.6864617607.
The cubic root of 20265181 is about 272.6361847695.
The spelling of 20265181 in words is "twenty million, two hundred sixty-five thousand, one hundred eighty-one".