28309545 has 24 divisors (see below), whose sum is σ = 53531712. Its totient is φ = 13725600.

The previous prime is 28309531. The next prime is 28309559. The reversal of 28309545 is 54590382.

It is an interprime number because it is at equal distance from previous prime (28309531) and next prime (28309559).

It is not a de Polignac number, because 28309545 - 2⁸ = 28309289 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28101 + ... + 29090.

It is an arithmetic number, because the mean of its divisors is an integer number (2230488).

Almost surely, 2^28309545 is an apocalyptic number.

It is an amenable number.

28309545 is a deficient number, since it is larger than the sum of its proper divisors (25222167).

28309545 is a wasteful number, since it uses less digits than its factorization.

28309545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57213 (or 57210 counting only the distinct ones).

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

The square root of 28309545 is about 5320.6714801799. The cubic root of 28309545 is about 304.7737998539.

The spelling of 28309545 in words is "twenty-eight million, three hundred nine thousand, five hundred forty-five".