28888945 has 4 divisors (see below), whose sum is σ = 34666740. Its totient is φ = 23111152.

The previous prime is 28888939. The next prime is 28888963. The reversal of 28888945 is 54988882.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4800481 + 24088464 = 2191^2 + 4908^2 .

It is a cyclic number.

It is not a de Polignac number, because 28888945 - 2¹⁷ = 28757873 is a prime.

It is a super-2 number, since 2×28888945² = 1669142286426050, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28888892 and 28888901.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2888890 + ... + 2888899.

It is an arithmetic number, because the mean of its divisors is an integer number (8666685).

Almost surely, 2^28888945 is an apocalyptic number.

It is an amenable number.

28888945 is a deficient number, since it is larger than the sum of its proper divisors (5777795).

28888945 is an equidigital number, since it uses as much as digits as its factorization.

28888945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5777794.

The product of its digits is 1474560, while the sum is 52.

The square root of 28888945 is about 5374.8437186582. The cubic root of 28888945 is about 306.8390014089.

The spelling of 28888945 in words is "twenty-eight million, eight hundred eighty-eight thousand, nine hundred forty-five".