64447487989 has 2 divisors, whose sum is σ = 64447487990. Its totient is φ = 64447487988.

The previous prime is 64447487987. The next prime is 64447488011. The reversal of 64447487989 is 98978474446.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 63637630225 + 809857764 = 252265^2 + 28458^2 .

It is a cyclic number.

It is not a de Polignac number, because 64447487989 - 2¹ = 64447487987 is a prime.

Together with 64447487987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64447487987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32223743994 + 32223743995.

It is an arithmetic number, because the mean of its divisors is an integer number (32223743995).

Almost surely, 2^64447487989 is an apocalyptic number.

It is an amenable number.

64447487989 is a deficient number, since it is larger than the sum of its proper divisors (1).

64447487989 is an equidigital number, since it uses as much as digits as its factorization.

64447487989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 390168576, while the sum is 70.

The spelling of 64447487989 in words is "sixty-four billion, four hundred forty-seven million, four hundred eighty-seven thousand, nine hundred eighty-nine".