28455309 has 12 divisors (see below), whose sum is σ = 41681952. Its totient is φ = 18702600.

The previous prime is 28455299. The next prime is 28455313. The reversal of 28455309 is 90355482.

It is not a de Polignac number, because 28455309 - 2⁵ = 28455277 is a prime.

It is a super-2 number, since 2×28455309² = 1619409220570962, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28455319) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21627 + ... + 22904.

It is an arithmetic number, because the mean of its divisors is an integer number (3473496).

Almost surely, 2^28455309 is an apocalyptic number.

It is an amenable number.

28455309 is a deficient number, since it is larger than the sum of its proper divisors (13226643).

28455309 is a wasteful number, since it uses less digits than its factorization.

28455309 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44608 (or 44605 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The square root of 28455309 is about 5334.3517881745. The cubic root of 28455309 is about 305.2959914362.

The spelling of 28455309 in words is "twenty-eight million, four hundred fifty-five thousand, three hundred nine".