28932217 has 4 divisors (see below), whose sum is σ = 28943460. Its totient is φ = 28920976.

The previous prime is 28932191. The next prime is 28932247. The reversal of 28932217 is 71223982.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 17480761 + 11451456 = 4181^2 + 3384^2 .

It is a cyclic number.

It is not a de Polignac number, because 28932217 - 2¹¹ = 28930169 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (28932247) 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, 363 + ... + 7615.

It is an arithmetic number, because the mean of its divisors is an integer number (7235865).

Almost surely, 2^28932217 is an apocalyptic number.

It is an amenable number.

28932217 is a deficient number, since it is larger than the sum of its proper divisors (11243).

28932217 is an equidigital number, since it uses as much as digits as its factorization.

28932217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11242.

The product of its digits is 12096, while the sum is 34.

The square root of 28932217 is about 5378.8676317604. The cubic root of 28932217 is about 306.9921270355.

The spelling of 28932217 in words is "twenty-eight million, nine hundred thirty-two thousand, two hundred seventeen".