28293215 has 4 divisors (see below), whose sum is σ = 33951864. Its totient is φ = 22634568.

The previous prime is 28293211. The next prime is 28293227. The reversal of 28293215 is 51239282.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 28293215 - 2² = 28293211 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28293211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2829317 + ... + 2829326.

It is an arithmetic number, because the mean of its divisors is an integer number (8487966).

Almost surely, 2^28293215 is an apocalyptic number.

28293215 is a deficient number, since it is larger than the sum of its proper divisors (5658649).

28293215 is an equidigital number, since it uses as much as digits as its factorization.

28293215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5658648.

The product of its digits is 8640, while the sum is 32.

The square root of 28293215 is about 5319.1366780710. The cubic root of 28293215 is about 304.7151869558.

The spelling of 28293215 in words is "twenty-eight million, two hundred ninety-three thousand, two hundred fifteen".