1985642564137 has 2 divisors, whose sum is σ = 1985642564138. Its totient is φ = 1985642564136.

The previous prime is 1985642564111. The next prime is 1985642564153. The reversal of 1985642564137 is 7314652465891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1120102605801 + 865539958336 = 1058349^2 + 930344^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1985642564137 is a prime.

It is not a weakly prime, because it can be changed into another prime (1985642564197) 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, 992821282068 + 992821282069.

It is an arithmetic number, because the mean of its divisors is an integer number (992821282069).

Almost surely, 2^{1985642564137} is an apocalyptic number.

It is an amenable number.

1985642564137 is a deficient number, since it is larger than the sum of its proper divisors (1).

1985642564137 is an equidigital number, since it uses as much as digits as its factorization.

1985642564137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 43545600, while the sum is 61.

The spelling of 1985642564137 in words is "one trillion, nine hundred eighty-five billion, six hundred forty-two million, five hundred sixty-four thousand, one hundred thirty-seven".