28389197 has 4 divisors (see below), whose sum is σ = 28435680. Its totient is φ = 28342716.

The previous prime is 28389161. The next prime is 28389209. The reversal of 28389197 is 79198382.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 79198382 = 2 ⋅39599191.

It is a cyclic number.

It is not a de Polignac number, because 28389197 - 2²⁴ = 11611981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28389157) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22313 + ... + 23550.

It is an arithmetic number, because the mean of its divisors is an integer number (7108920).

Almost surely, 2^28389197 is an apocalyptic number.

It is an amenable number.

28389197 is a deficient number, since it is larger than the sum of its proper divisors (46483).

28389197 is an equidigital number, since it uses as much as digits as its factorization.

28389197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46482.

The product of its digits is 217728, while the sum is 47.

The square root of 28389197 is about 5328.1513679699. The cubic root of 28389197 is about 305.0593703290.

The spelling of 28389197 in words is "twenty-eight million, three hundred eighty-nine thousand, one hundred ninety-seven".