28105219 has 8 divisors (see below), whose sum is σ = 28587680. Its totient is φ = 27625536.

The previous prime is 28105183. The next prime is 28105229. The reversal of 28105219 is 91250182.

28105219 = 1² + 2² + ... + 438².

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

It is a de Polignac number, because none of the positive numbers 2^k-28105219 is a prime.

It is a super-2 number, since 2×28105219² = 1579806670075922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28105229) 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, 31609 + ... + 32485.

It is an arithmetic number, because the mean of its divisors is an integer number (3573460).

Almost surely, 2^28105219 is an apocalyptic number.

28105219 is a deficient number, since it is larger than the sum of its proper divisors (482461).

28105219 is an equidigital number, since it uses as much as digits as its factorization.

28105219 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1389.

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 28105219 is about 5301.4355602987. The cubic root of 28105219 is about 304.0387870351.

The spelling of 28105219 in words is "twenty-eight million, one hundred five thousand, two hundred nineteen".