28205397 has 24 divisors (see below), whose sum is σ = 47062080. Its totient is φ = 16087680.

The previous prime is 28205393. The next prime is 28205407. The reversal of 28205397 is 79350282.

It is a happy number.

It is not a de Polignac number, because 28205397 - 2² = 28205393 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28205393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6697 + ... + 10062.

It is an arithmetic number, because the mean of its divisors is an integer number (1960920).

Almost surely, 2^28205397 is an apocalyptic number.

It is an amenable number.

28205397 is a deficient number, since it is larger than the sum of its proper divisors (18856683).

28205397 is a wasteful number, since it uses less digits than its factorization.

28205397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16793 (or 16790 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 28205397 is about 5310.8753515781. The cubic root of 28205397 is about 304.3995964281.

The spelling of 28205397 in words is "twenty-eight million, two hundred five thousand, three hundred ninety-seven".