28181287 has 2 divisors, whose sum is σ = 28181288. Its totient is φ = 28181286.

The previous prime is 28181203. The next prime is 28181299. The reversal of 28181287 is 78218182.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28181287 - 2⁷ = 28181159 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28181687) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14090643 + 14090644.

It is an arithmetic number, because the mean of its divisors is an integer number (14090644).

Almost surely, 2^28181287 is an apocalyptic number.

28181287 is a deficient number, since it is larger than the sum of its proper divisors (1).

28181287 is an equidigital number, since it uses as much as digits as its factorization.

28181287 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14336, while the sum is 37.

The square root of 28181287 is about 5308.6049956651. The cubic root of 28181287 is about 304.3128380155.

The spelling of 28181287 in words is "twenty-eight million, one hundred eighty-one thousand, two hundred eighty-seven".