28998215 has 8 divisors (see below), whose sum is σ = 34832160. Its totient is φ = 23175712.

The previous prime is 28998197. The next prime is 28998217. The reversal of 28998215 is 51289982.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28998215 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28998217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4397 + ... + 8793.

It is an arithmetic number, because the mean of its divisors is an integer number (4354020).

Almost surely, 2^28998215 is an apocalyptic number.

28998215 is the 4397-th pentagonal number.

28998215 is a deficient number, since it is larger than the sum of its proper divisors (5833945).

28998215 is a wasteful number, since it uses less digits than its factorization.

28998215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5721.

The product of its digits is 103680, while the sum is 44.

The square root of 28998215 is about 5384.9990714948. Note that the first 3 decimals coincide. The cubic root of 28998215 is about 307.2253788927.

The spelling of 28998215 in words is "twenty-eight million, nine hundred ninety-eight thousand, two hundred fifteen".