1280564403761 has 4 divisors (see below), whose sum is σ = 1336241116992. Its totient is φ = 1224887690532.

The previous prime is 1280564403749. The next prime is 1280564403779. The reversal of 1280564403761 is 1673044650821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1280564403761 - 2¹⁰ = 1280564402737 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1280564403361) 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 3 ways as a sum of consecutive naturals, for example, 27838356581 + ... + 27838356626.

It is an arithmetic number, because the mean of its divisors is an integer number (334060279248).

Almost surely, 2^{1280564403761} is an apocalyptic number.

It is an amenable number.

1280564403761 is a deficient number, since it is larger than the sum of its proper divisors (55676713231).

1280564403761 is an equidigital number, since it uses as much as digits as its factorization.

1280564403761 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55676713230.

The product of its (nonzero) digits is 967680, while the sum is 47.

The spelling of 1280564403761 in words is "one trillion, two hundred eighty billion, five hundred sixty-four million, four hundred three thousand, seven hundred sixty-one".