64981789 has 2 divisors, whose sum is σ = 64981790. Its totient is φ = 64981788.

The previous prime is 64981783. The next prime is 64981799. The reversal of 64981789 is 98718946.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 64673764 + 308025 = 8042^2 + 555^2 .

It is a cyclic number.

It is not a de Polignac number, because 64981789 - 2¹¹ = 64979741 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64981783) 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, 32490894 + 32490895.

It is an arithmetic number, because the mean of its divisors is an integer number (32490895).

Almost surely, 2^64981789 is an apocalyptic number.

It is an amenable number.

64981789 is a deficient number, since it is larger than the sum of its proper divisors (1).

64981789 is an equidigital number, since it uses as much as digits as its factorization.

64981789 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 870912, while the sum is 52.

The square root of 64981789 is about 8061.1282709060. The cubic root of 64981789 is about 402.0350228969.

The spelling of 64981789 in words is "sixty-four million, nine hundred eighty-one thousand, seven hundred eighty-nine".