2857320665 has 4 divisors (see below), whose sum is σ = 3428784804. Its totient is φ = 2285856528.

The previous prime is 2857320647. The next prime is 2857320673. The reversal of 2857320665 is 5660237582.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1743563536 + 1113757129 = 41756^2 + 33373^2 .

It is a cyclic number.

It is not a de Polignac number, because 2857320665 - 2⁸ = 2857320409 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 285732062 + ... + 285732071.

It is an arithmetic number, because the mean of its divisors is an integer number (857196201).

Almost surely, 2^2857320665 is an apocalyptic number.

It is an amenable number.

2857320665 is a deficient number, since it is larger than the sum of its proper divisors (571464139).

2857320665 is an equidigital number, since it uses as much as digits as its factorization.

2857320665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 571464138.

The product of its (nonzero) digits is 604800, while the sum is 44.

The square root of 2857320665 is about 53453.9115968139. The cubic root of 2857320665 is about 1419.0128471064.

The spelling of 2857320665 in words is "two billion, eight hundred fifty-seven million, three hundred twenty thousand, six hundred sixty-five".