28204391 has 2 divisors, whose sum is σ = 28204392. Its totient is φ = 28204390.

The previous prime is 28204369. The next prime is 28204409. The reversal of 28204391 is 19340282.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 28204391 - 2¹⁴ = 28188007 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 (28204331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14102195 + 14102196.

It is an arithmetic number, because the mean of its divisors is an integer number (14102196).

Almost surely, 2^28204391 is an apocalyptic number.

28204391 is a deficient number, since it is larger than the sum of its proper divisors (1).

28204391 is an equidigital number, since it uses as much as digits as its factorization.

28204391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 28204391 is about 5310.7806394164. The cubic root of 28204391 is about 304.3959773851.

The spelling of 28204391 in words is "twenty-eight million, two hundred four thousand, three hundred ninety-one".