1321007785 has 8 divisors (see below), whose sum is σ = 1600905096. Its totient is φ = 1046342400.

The previous prime is 1321007777. The next prime is 1321007791. The reversal of 1321007785 is 5877001231.

It can be written as a sum of positive squares in 4 ways, for example, as 191241241 + 1129766544 = 13829^2 + 33612^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1321007785 - 2³ = 1321007777 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1321007785.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1307424 + ... + 1308433.

It is an arithmetic number, because the mean of its divisors is an integer number (200113137).

Almost surely, 2^1321007785 is an apocalyptic number.

It is an amenable number.

1321007785 is a deficient number, since it is larger than the sum of its proper divisors (279897311).

1321007785 is a wasteful number, since it uses less digits than its factorization.

1321007785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2615963.

The product of its (nonzero) digits is 11760, while the sum is 34.

The square root of 1321007785 is about 36345.6707875917. The cubic root of 1321007785 is about 1097.2404064293.

The spelling of 1321007785 in words is "one billion, three hundred twenty-one million, seven thousand, seven hundred eighty-five".