1321260671666 has 32 divisors (see below), whose sum is σ = 2146603299456. Its totient is φ = 606318048000.

The previous prime is 1321260671663. The next prime is 1321260671699. The reversal of 1321260671666 is 6661760621231.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1321260671666.

It is not an unprimeable number, because it can be changed into a prime (1321260671663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3786761 + ... + 4120931.

It is an arithmetic number, because the mean of its divisors is an integer number (67081353108).

Almost surely, 2^{1321260671666} is an apocalyptic number.

1321260671666 is a deficient number, since it is larger than the sum of its proper divisors (825342627790).

1321260671666 is a wasteful number, since it uses less digits than its factorization.

1321260671666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 335058.

The product of its (nonzero) digits is 653184, while the sum is 47.

The spelling of 1321260671666 in words is "one trillion, three hundred twenty-one billion, two hundred sixty million, six hundred seventy-one thousand, six hundred sixty-six".