28108643 has 2 divisors, whose sum is σ = 28108644. Its totient is φ = 28108642.

The previous prime is 28108621. The next prime is 28108649. The reversal of 28108643 is 34680182.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28108643 - 2²² = 23914339 is a prime.

It is a super-2 number, since 2×28108643² = 1580191622602898, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (28108649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14054321 + 14054322.

It is an arithmetic number, because the mean of its divisors is an integer number (14054322).

Almost surely, 2^28108643 is an apocalyptic number.

28108643 is a deficient number, since it is larger than the sum of its proper divisors (1).

28108643 is an equidigital number, since it uses as much as digits as its factorization.

28108643 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9216, while the sum is 32.

The square root of 28108643 is about 5301.7584818624. The cubic root of 28108643 is about 304.0511333367.

The spelling of 28108643 in words is "twenty-eight million, one hundred eight thousand, six hundred forty-three".