64843199989 has 2 divisors, whose sum is σ = 64843199990. Its totient is φ = 64843199988.

The previous prime is 64843199917. The next prime is 64843200001. The reversal of 64843199989 is 98999134846.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 33925956100 + 30917243889 = 184190^2 + 175833^2 .

It is a cyclic number.

It is not a de Polignac number, because 64843199989 - 2²⁵ = 64809645557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64843199089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32421599994 + 32421599995.

It is an arithmetic number, because the mean of its divisors is an integer number (32421599995).

Almost surely, 2^64843199989 is an apocalyptic number.

It is an amenable number.

64843199989 is a deficient number, since it is larger than the sum of its proper divisors (1).

64843199989 is an equidigital number, since it uses as much as digits as its factorization.

64843199989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120932352, while the sum is 70.

The spelling of 64843199989 in words is "sixty-four billion, eight hundred forty-three million, one hundred ninety-nine thousand, nine hundred eighty-nine".