28644331 has 2 divisors, whose sum is σ = 28644332. Its totient is φ = 28644330.

The previous prime is 28644313. The next prime is 28644347. The reversal of 28644331 is 13344682.

Together with previous prime (28644313) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28644331 - 2⁹ = 28643819 is a prime.

It is a super-2 number, since 2×28644331² = 1640995396875122, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 28644293 and 28644302.

It is not a weakly prime, because it can be changed into another prime (28644731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14322165 + 14322166.

It is an arithmetic number, because the mean of its divisors is an integer number (14322166).

Almost surely, 2^28644331 is an apocalyptic number.

28644331 is a deficient number, since it is larger than the sum of its proper divisors (1).

28644331 is an equidigital number, since it uses as much as digits as its factorization.

28644331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13824, while the sum is 31.

The square root of 28644331 is about 5352.0398914806. The cubic root of 28644331 is about 305.9705035148.

The spelling of 28644331 in words is "twenty-eight million, six hundred forty-four thousand, three hundred thirty-one".