1640706465449 has 2 divisors, whose sum is σ = 1640706465450. Its totient is φ = 1640706465448.

The previous prime is 1640706465401. The next prime is 1640706465481. The reversal of 1640706465449 is 9445646070461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1441183443049 + 199523022400 = 1200493^2 + 446680^2 .

It is a cyclic number.

It is not a de Polignac number, because 1640706465449 - 2¹² = 1640706461353 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1640706465394 and 1640706465403.

It is not a weakly prime, because it can be changed into another prime (1640706465949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820353232724 + 820353232725.

It is an arithmetic number, because the mean of its divisors is an integer number (820353232725).

Almost surely, 2^{1640706465449} is an apocalyptic number.

It is an amenable number.

1640706465449 is a deficient number, since it is larger than the sum of its proper divisors (1).

1640706465449 is an equidigital number, since it uses as much as digits as its factorization.

1640706465449 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 17418240, while the sum is 56.

The spelling of 1640706465449 in words is "one trillion, six hundred forty billion, seven hundred six million, four hundred sixty-five thousand, four hundred forty-nine".