28320645 has 8 divisors (see below), whose sum is σ = 45313056. Its totient is φ = 15104336.

The previous prime is 28320641. The next prime is 28320647. The reversal of 28320645 is 54602382.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 28320645 - 2² = 28320641 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28320641) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 944007 + ... + 944036.

It is an arithmetic number, because the mean of its divisors is an integer number (5664132).

Almost surely, 2^28320645 is an apocalyptic number.

It is an amenable number.

28320645 is a deficient number, since it is larger than the sum of its proper divisors (16992411).

28320645 is a wasteful number, since it uses less digits than its factorization.

28320645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1888051.

The product of its (nonzero) digits is 11520, while the sum is 30.

The square root of 28320645 is about 5321.7144793760. The cubic root of 28320645 is about 304.8136279651.

The spelling of 28320645 in words is "twenty-eight million, three hundred twenty thousand, six hundred forty-five".