64786481489981 has 2 divisors, whose sum is σ = 64786481489982. Its totient is φ = 64786481489980.

The previous prime is 64786481489923. The next prime is 64786481490037. The reversal of 64786481489981 is 18998418468746.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 64031059767481 + 755421722500 = 8001941^2 + 869150^2 .

It is a cyclic number.

It is not a de Polignac number, because 64786481489981 - 2¹⁰ = 64786481488957 is a prime.

It is a super-2 number, since 2×64786481489981² (a number of 28 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 64786481489981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64786481479981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32393240744990 + 32393240744991.

It is an arithmetic number, because the mean of its divisors is an integer number (32393240744991).

Almost surely, 2^{64786481489981} is an apocalyptic number.

It is an amenable number.

64786481489981 is a deficient number, since it is larger than the sum of its proper divisors (1).

64786481489981 is an equidigital number, since it uses as much as digits as its factorization.

64786481489981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5350883328, while the sum is 83.

The spelling of 64786481489981 in words is "sixty-four trillion, seven hundred eighty-six billion, four hundred eighty-one million, four hundred eighty-nine thousand, nine hundred eighty-one".