2078443865 has 4 divisors (see below), whose sum is σ = 2494132644. Its totient is φ = 1662755088.

The previous prime is 2078443859. The next prime is 2078443889. The reversal of 2078443865 is 5683448702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5683448702 = 2 ⋅2841724351.

It can be written as a sum of positive squares in 2 ways, for example, as 419266576 + 1659177289 = 20476^2 + 40733^2 .

It is a cyclic number.

It is not a de Polignac number, because 2078443865 - 2⁴ = 2078443849 is a prime.

It is a super-2 number, since 2×2078443865² = 8639857799912276450, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 207844382 + ... + 207844391.

It is an arithmetic number, because the mean of its divisors is an integer number (623533161).

Almost surely, 2^2078443865 is an apocalyptic number.

It is an amenable number.

2078443865 is a deficient number, since it is larger than the sum of its proper divisors (415688779).

2078443865 is an equidigital number, since it uses as much as digits as its factorization.

2078443865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 415688778.

The product of its (nonzero) digits is 1290240, while the sum is 47.

The square root of 2078443865 is about 45589.9535533872. The cubic root of 2078443865 is about 1276.1824457907.

The spelling of 2078443865 in words is "two billion, seventy-eight million, four hundred forty-three thousand, eight hundred sixty-five".