6540641273 has 2 divisors, whose sum is σ = 6540641274. Its totient is φ = 6540641272.

The previous prime is 6540641267. The next prime is 6540641287. The reversal of 6540641273 is 3721460456.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3349747129 + 3190894144 = 57877^2 + 56488^2 .

It is a cyclic number.

It is not a de Polignac number, because 6540641273 - 2⁶ = 6540641209 is a prime.

It is not a weakly prime, because it can be changed into another prime (6540641203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3270320636 + 3270320637.

It is an arithmetic number, because the mean of its divisors is an integer number (3270320637).

Almost surely, 2^6540641273 is an apocalyptic number.

It is an amenable number.

6540641273 is a deficient number, since it is larger than the sum of its proper divisors (1).

6540641273 is an equidigital number, since it uses as much as digits as its factorization.

6540641273 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 120960, while the sum is 38.

The square root of 6540641273 is about 80874.2312050013. The cubic root of 6540641273 is about 1870.1370897619.

The spelling of 6540641273 in words is "six billion, five hundred forty million, six hundred forty-one thousand, two hundred seventy-three".