66065556061591 has 2 divisors, whose sum is σ = 66065556061592. Its totient is φ = 66065556061590.

The previous prime is 66065556061499. The next prime is 66065556061607. The reversal of 66065556061591 is 19516065556066.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66065556061591 - 2³³ = 66056966126999 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66065556061691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33032778030795 + 33032778030796.

It is an arithmetic number, because the mean of its divisors is an integer number (33032778030796).

Almost surely, 2^{66065556061591} is an apocalyptic number.

66065556061591 is a deficient number, since it is larger than the sum of its proper divisors (1).

66065556061591 is an equidigital number, since it uses as much as digits as its factorization.

66065556061591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43740000, while the sum is 61.

The spelling of 66065556061591 in words is "sixty-six trillion, sixty-five billion, five hundred fifty-six million, sixty-one thousand, five hundred ninety-one".