64642443999949 has 2 divisors, whose sum is σ = 64642443999950. Its totient is φ = 64642443999948.

The previous prime is 64642443999823. The next prime is 64642444000159. The reversal of 64642443999949 is 94999934424646.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 60114932437924 + 4527511562025 = 7753382^2 + 2127795^2 .

It is a cyclic number.

It is not a de Polignac number, because 64642443999949 - 2¹⁵ = 64642443967181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64642443399949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32321221999974 + 32321221999975.

It is an arithmetic number, because the mean of its divisors is an integer number (32321221999975).

Almost surely, 2^{64642443999949} is an apocalyptic number.

It is an amenable number.

64642443999949 is a deficient number, since it is larger than the sum of its proper divisors (1).

64642443999949 is an equidigital number, since it uses as much as digits as its factorization.

64642443999949 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13060694016, while the sum is 82.

The spelling of 64642443999949 in words is "sixty-four trillion, six hundred forty-two billion, four hundred forty-three million, nine hundred ninety-nine thousand, nine hundred forty-nine".