28031218 has 8 divisors (see below), whose sum is σ = 42440112. Its totient is φ = 13884516.

The previous prime is 28031191. The next prime is 28031239. The reversal of 28031218 is 81213082.

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

It is a junction number, because it is equal to n+sod(n) for n = 28031192 and 28031201.

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, 65280 + ... + 65707.

It is an arithmetic number, because the mean of its divisors is an integer number (5305014).

Almost surely, 2^28031218 is an apocalyptic number.

28031218 is a deficient number, since it is larger than the sum of its proper divisors (14408894).

28031218 is a wasteful number, since it uses less digits than its factorization.

28031218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131096.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 28031218 is about 5294.4516241061. The cubic root of 28031218 is about 303.7717079328.

The spelling of 28031218 in words is "twenty-eight million, thirty-one thousand, two hundred eighteen".