1285518644489 has 2 divisors, whose sum is σ = 1285518644490. Its totient is φ = 1285518644488.

The previous prime is 1285518644467. The next prime is 1285518644537. The reversal of 1285518644489 is 9844468155821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1160402928400 + 125115716089 = 1077220^2 + 353717^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1285518644489 is a prime.

It is a super-2 number, since 2×1285518644489² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1285518644089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 642759322244 + 642759322245.

It is an arithmetic number, because the mean of its divisors is an integer number (642759322245).

Almost surely, 2^{1285518644489} is an apocalyptic number.

It is an amenable number.

1285518644489 is a deficient number, since it is larger than the sum of its proper divisors (1).

1285518644489 is an equidigital number, since it uses as much as digits as its factorization.

1285518644489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 88473600, while the sum is 65.

The spelling of 1285518644489 in words is "one trillion, two hundred eighty-five billion, five hundred eighteen million, six hundred forty-four thousand, four hundred eighty-nine".