6484438781 has 2 divisors, whose sum is σ = 6484438782. Its totient is φ = 6484438780.

The previous prime is 6484438757. The next prime is 6484438853. The reversal of 6484438781 is 1878344846.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 5510686756 + 973752025 = 74234^2 + 31205^2 .

It is a cyclic number.

It is not a de Polignac number, because 6484438781 - 2¹⁸ = 6484176637 is a prime.

It is a super-2 number, since 2×6484438781² = 84095892609073531922, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6484438711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3242219390 + 3242219391.

It is an arithmetic number, because the mean of its divisors is an integer number (3242219391).

Almost surely, 2^6484438781 is an apocalyptic number.

It is an amenable number.

6484438781 is a deficient number, since it is larger than the sum of its proper divisors (1).

6484438781 is an equidigital number, since it uses as much as digits as its factorization.

6484438781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4128768, while the sum is 53.

The square root of 6484438781 is about 80526.0130703116. The cubic root of 6484438781 is about 1864.7650954419.

The spelling of 6484438781 in words is "six billion, four hundred eighty-four million, four hundred thirty-eight thousand, seven hundred eighty-one".