28815893 has 2 divisors, whose sum is σ = 28815894. Its totient is φ = 28815892.

The previous prime is 28815889. The next prime is 28815923. The reversal of 28815893 is 39851882.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 26450449 + 2365444 = 5143^2 + 1538^2 .

It is a cyclic number.

It is not a de Polignac number, because 28815893 - 2² = 28815889 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28815823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14407946 + 14407947.

It is an arithmetic number, because the mean of its divisors is an integer number (14407947).

Almost surely, 2^28815893 is an apocalyptic number.

It is an amenable number.

28815893 is a deficient number, since it is larger than the sum of its proper divisors (1).

28815893 is an equidigital number, since it uses as much as digits as its factorization.

28815893 is an evil number, because the sum of its binary digits is even.

The product of its digits is 138240, while the sum is 44.

The square root of 28815893 is about 5368.0436846211. The cubic root of 28815893 is about 306.5801466436.

The spelling of 28815893 in words is "twenty-eight million, eight hundred fifteen thousand, eight hundred ninety-three".