28282021 has 2 divisors, whose sum is σ = 28282022. Its totient is φ = 28282020.

The previous prime is 28281991. The next prime is 28282043. The reversal of 28282021 is 12028282.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 24900100 + 3381921 = 4990^2 + 1839^2 .

It is a cyclic number.

It is not a de Polignac number, because 28282021 - 2¹⁵ = 28249253 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28285021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14141010 + 14141011.

It is an arithmetic number, because the mean of its divisors is an integer number (14141011).

Almost surely, 2^28282021 is an apocalyptic number.

It is an amenable number.

28282021 is a deficient number, since it is larger than the sum of its proper divisors (1).

28282021 is an equidigital number, since it uses as much as digits as its factorization.

28282021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1024, while the sum is 25.

The square root of 28282021 is about 5318.0843355479. The cubic root of 28282021 is about 304.6749955561.

The spelling of 28282021 in words is "twenty-eight million, two hundred eighty-two thousand, twenty-one".