643914585427 has 2 divisors, whose sum is σ = 643914585428. Its totient is φ = 643914585426.

The previous prime is 643914585397. The next prime is 643914585481. The reversal of 643914585427 is 724585419346.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 643914585427 - 2³⁵ = 609554847059 is a prime.

It is not a weakly prime, because it can be changed into another prime (643914585497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321957292713 + 321957292714.

It is an arithmetic number, because the mean of its divisors is an integer number (321957292714).

Almost surely, 2^643914585427 is an apocalyptic number.

643914585427 is a deficient number, since it is larger than the sum of its proper divisors (1).

643914585427 is an equidigital number, since it uses as much as digits as its factorization.

643914585427 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 29030400, while the sum is 58.

The spelling of 643914585427 in words is "six hundred forty-three billion, nine hundred fourteen million, five hundred eighty-five thousand, four hundred twenty-seven".