1985642564263 has 2 divisors, whose sum is σ = 1985642564264. Its totient is φ = 1985642564262.

The previous prime is 1985642564197. The next prime is 1985642564309. The reversal of 1985642564263 is 3624652465891.

It is a strong prime.

It is an emirp because it is prime and its reverse (3624652465891) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1985642564263 - 2¹⁷ = 1985642433191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1985642564963) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 992821282131 + 992821282132.

It is an arithmetic number, because the mean of its divisors is an integer number (992821282132).

Almost surely, 2^{1985642564263} is an apocalyptic number.

1985642564263 is a deficient number, since it is larger than the sum of its proper divisors (1).

1985642564263 is an equidigital number, since it uses as much as digits as its factorization.

1985642564263 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 74649600, while the sum is 61.

The spelling of 1985642564263 in words is "one trillion, nine hundred eighty-five billion, six hundred forty-two million, five hundred sixty-four thousand, two hundred sixty-three".