28843226206921 has 27 divisors (see below), whose sum is σ = 35642878275207. Its totient is φ = 23267969430720.

The previous prime is 28843226206913. The next prime is 28843226206967. The reversal of 28843226206921 is 12960262234882.

The square root of 28843226206921 is 5370589.

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., 22455798950025 + 6387427256896 = 4738755^2 + 2527336^2 .

It is not a de Polignac number, because 28843226206921 - 2³ = 28843226206913 is a prime.

It is a super-2 number, since 2×28843226206921² (a number of 28 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28843226206321) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 639077526 + ... + 639122656.

Almost surely, 2^{28843226206921} is an apocalyptic number.

28843226206921 is the 5370589-th square number.

28843226206921 is the 2685295-th centered octagonal number.

It is an amenable number.

28843226206921 is a deficient number, since it is larger than the sum of its proper divisors (6799652068286).

28843226206921 is an frugal number, since it uses more digits than its factorization.

28843226206921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90310 (or 45155 counting only the distinct ones).

The product of its (nonzero) digits is 7962624, while the sum is 55.

The spelling of 28843226206921 in words is "twenty-eight trillion, eight hundred forty-three billion, two hundred twenty-six million, two hundred six thousand, nine hundred twenty-one".