28304413 has 4 divisors (see below), whose sum is σ = 28317600. Its totient is φ = 28291228.

The previous prime is 28304407. The next prime is 28304429. The reversal of 28304413 is 31440382.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 31440382 = 2 ⋅15720191.

It is a cyclic number.

It is not a de Polignac number, because 28304413 - 2¹³ = 28296221 is a prime.

It is a super-2 number, since 2×28304413² = 1602279590549138, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28304453) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2545 + ... + 7942.

It is an arithmetic number, because the mean of its divisors is an integer number (7079400).

Almost surely, 2^28304413 is an apocalyptic number.

It is an amenable number.

28304413 is a deficient number, since it is larger than the sum of its proper divisors (13187).

28304413 is a wasteful number, since it uses less digits than its factorization.

28304413 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13186.

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 28304413 is about 5320.1891883654. The cubic root of 28304413 is about 304.7553821122.

Adding to 28304413 its reverse (31440382), we get a palindrome (59744795).

The spelling of 28304413 in words is "twenty-eight million, three hundred four thousand, four hundred thirteen".