28321145 has 8 divisors (see below), whose sum is σ = 34075080. Its totient is φ = 22597120.

The previous prime is 28321129. The next prime is 28321159. The reversal of 28321145 is 54112382.

It can be written as a sum of positive squares in 4 ways, for example, as 4477456 + 23843689 = 2116^2 + 4883^2 .

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

It is not a de Polignac number, because 28321145 - 2⁴ = 28321129 is a prime.

It is a super-2 number, since 2×28321145² = 1604174508222050, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5336 + ... + 9225.

It is an arithmetic number, because the mean of its divisors is an integer number (4259385).

Almost surely, 2^28321145 is an apocalyptic number.

It is an amenable number.

28321145 is a deficient number, since it is larger than the sum of its proper divisors (5753935).

28321145 is a wasteful number, since it uses less digits than its factorization.

28321145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14955.

The product of its digits is 1920, while the sum is 26.

The square root of 28321145 is about 5321.7614565104. The cubic root of 28321145 is about 304.8154217792.

The spelling of 28321145 in words is "twenty-eight million, three hundred twenty-one thousand, one hundred forty-five".