28270391 has 2 divisors, whose sum is σ = 28270392. Its totient is φ = 28270390.

The previous prime is 28270367. The next prime is 28270421. The reversal of 28270391 is 19307282.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28270391 - 2¹⁸ = 28008247 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 (28270301) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14135195 + 14135196.

It is an arithmetic number, because the mean of its divisors is an integer number (14135196).

Almost surely, 2^28270391 is an apocalyptic number.

28270391 is a deficient number, since it is larger than the sum of its proper divisors (1).

28270391 is an equidigital number, since it uses as much as digits as its factorization.

28270391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 28270391 is about 5316.9907842689. The cubic root of 28270391 is about 304.6332274895.

The spelling of 28270391 in words is "twenty-eight million, two hundred seventy thousand, three hundred ninety-one".