66610278887 has 2 divisors, whose sum is σ = 66610278888. Its totient is φ = 66610278886.

The previous prime is 66610278857. The next prime is 66610278929. The reversal of 66610278887 is 78887201666.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 66610278887 - 2¹⁴ = 66610262503 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66610278857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33305139443 + 33305139444.

It is an arithmetic number, because the mean of its divisors is an integer number (33305139444).

Almost surely, 2^66610278887 is an apocalyptic number.

66610278887 is a deficient number, since it is larger than the sum of its proper divisors (1).

66610278887 is an equidigital number, since it uses as much as digits as its factorization.

66610278887 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10838016, while the sum is 59.

The spelling of 66610278887 in words is "sixty-six billion, six hundred ten million, two hundred seventy-eight thousand, eight hundred eighty-seven".