2820778321 has 9 divisors (see below), whose sum is σ = 2846449371. Its totient is φ = 2795338152.

The previous prime is 2820778313. The next prime is 2820778369. The reversal of 2820778321 is 1238770282.

The square root of 2820778321 is 53111.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 2565929025 + 254849296 = 50655^2 + 15964^2 .

It is not a de Polignac number, because 2820778321 - 2³ = 2820778313 is a prime.

It is a super-3 number, since 3×2820778321³ (a number of 29 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2820778021) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 9188050 + ... + 9188356.

Almost surely, 2^2820778321 is an apocalyptic number.

2820778321 is the 53111-st square number.

2820778321 is the 26556-th centered octagonal number.

It is an amenable number.

2820778321 is a deficient number, since it is larger than the sum of its proper divisors (25671050).

2820778321 is an frugal number, since it uses more digits than its factorization.

2820778321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 960 (or 480 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 40.

The cubic root of 2820778321 is about 1412.9376108882.

The spelling of 2820778321 in words is "two billion, eight hundred twenty million, seven hundred seventy-eight thousand, three hundred twenty-one".