6416820181 has 2 divisors, whose sum is σ = 6416820182. Its totient is φ = 6416820180.

The previous prime is 6416820149. The next prime is 6416820259. The reversal of 6416820181 is 1810286146.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5164721956 + 1252098225 = 71866^2 + 35385^2 .

It is a cyclic number.

It is not a de Polignac number, because 6416820181 - 2⁵ = 6416820149 is a prime.

It is a super-2 number, since 2×6416820181² = 82351162470577745522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 6416820181.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6416820121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3208410090 + 3208410091.

It is an arithmetic number, because the mean of its divisors is an integer number (3208410091).

Almost surely, 2^6416820181 is an apocalyptic number.

It is an amenable number.

6416820181 is a deficient number, since it is larger than the sum of its proper divisors (1).

6416820181 is an equidigital number, since it uses as much as digits as its factorization.

6416820181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 18432, while the sum is 37.

The square root of 6416820181 is about 80105.0571499703. The cubic root of 6416820181 is about 1858.2606182080.

The spelling of 6416820181 in words is "six billion, four hundred sixteen million, eight hundred twenty thousand, one hundred eighty-one".